Physics 1 Final Exam Review—All Practice Quizzes

c) the frequency of radiation emitted by cesium atoms

The current definition of the standard second of time is based on

a) Earths rotation rate

b) the oscillation of a particular pendulum kept in france

c) the frequency of radiation emitted by cesium atoms

d) the duration of one year

a) greater than 15

If a tree is 15 m tall, its height expressed in feet is x ft, where x it

a) greater than 15

b) less than 15

d) Vectors →A and →B are in opposite directions.

Under what condition is |(→A)−(→B)|=A+B?

a) Vectors →A and →B are in the same direction.

b) Vectors →A and →B are in perpendicular directions.

c) The statement is never true.

d) Vectors →A and →B are in opposite directions.

e) The magnitude of vector →B is zero.

c) The magnitude of vector →A is equal to the magnitude of vector →B.

If the eastward component of vector →A is equal to the westward component of vector →B and their northward components are equal. Which one of the following statements about these two vectors is correct?

a) Vector →A is perpendicular to vector →B.

b) The magnitude of vector →A is twice the magnitude of vector →B.

c) The magnitude of vector →A is equal to the magnitude of vector →B.

d) Vectors →A and →B point in opposite directions.

e) Vector →A is parallel to vector →B.

False

True or False - If two nonzero vectors point in the same direction, their dot product must be zero.

c) 206.3

What is the value of π(8.104)^2, written with the correct number of significant figures?

a) 200

b) 206.324

c) 206.3

d) 206

e) 206.323

e) 1.3

What is the difference between 103.5 and 102.24 written with the correct number of significant figures?

a) 1.2600

b) 1

c) 1.26

d) 1.260

e) 1.3

c) 0.348

What is 0.2052/3, expressed to the proper number of significant figures?

a) 0.3

b) 0.35

c) 0.348

d) 0.3477

c) 0.682m^2.

The length and width of a rectangle are 1.125 m and 0.606 m, respectively. Multiplying, your calculator gives the product as 0.68175. Rounding properly to the correct number of significant figures, the area should be written as

a) 0.7m^2.

b) 0.68m^2.

c) 0.682m^2.

d) 0.68175m^2.

e) 0.6818m^2.

c) 3.8 m/s.

In addition to 1m=39.37in, the following exact conversion equivalents are given: 1mile=5280ft, 1hour=60min, and 1min=60s. If a particle has a velocity of 8.4miles per hour, its velocity, in m/s, is closest to

a) 4.1 m/s.

b) 3.4 m/s.

c) 3.8 m/s.

d) 4.5 m/s.

e) 3.0 m/s.

b) 2.3×104m^2

A plot of land contains 5.8acres. How many square meters does it contain? [1acre=43,560ft2]

a) 7.1×103m^2

b) 2.3×104m^2

c) 7.0×104m^2

d) 5.0×104m^2

b) 4×10^7

Approximately how many times does an average human heart beat in a year?

a) 4×10^6

b) 4×10^7

c) 4×10^5

d) 4×10^8

e) 4×10^9

a) 5×10^4

Estimate the number of pennies that would fit in a box one foot long by one foot wide by one foot tall.

a) 5×10^4

b) 5×10^3

c) 5×10^5

d) 5×10^6

e) 5×10^2

e) √(ℓ/g)

The period of a pendulum is the time it takes the pendulum to swing back and forth once. If the only dimensional quantities that the period depends on are the acceleration of gravity, g, and the length of the pendulum, ℓ, what combination of g and ℓ must the period be proportional to? (Acceleration has SI units of m⋅s^−2.)

a) g/ℓ

b) √(gℓ)

c) gℓ^2

d) gℓ

e) √(ℓ/g)

b) F/μ

The speed of a wave pulse on a string depends on the tension, F, in the string and the mass per unit length, μ, of the string. Tension has SI units of kg⋅m⋅s^−2 and the mass per unit length has SI units of kg⋅m^−1. What combination of F and μ must the speed of the wave be proportional to?

a) √(μ/F)

b) F/μ

c) μ/F

d) √(F/μ)

e) √(μF)

a) 63°N of E

You walk 53m to the north, then turn 60° to your right and walk another 45m. Determine the direction of your displacement vector. Express your answer as an angle relative to east.

a) 63°N of E

b) 57°N of E

c) 50°N of E

d) 69°N of E

b) 8.9 m/s

A helicopter is flying horizontally with a speed of 444 m/s over a hill that slopes upward with a 2% grade (that is, the "rise" is 2% of the "run"). What is the component of the helicopter's velocity perpendicular to the sloping surface of the hill?

a) 220 m/s

b) 8.9 m/s

c) 435 m/s

d) 444 m/s

c) 3.61 in a direction 33.7° counterclockwise from the positive x-axis

Vector (→A)=−1.00ˆi+−2.00ˆj and vector (→B)=3.00ˆi+4.00ˆj. What are the magnitude and direction of vector (→C)=3.00(→A)+4.00(→B) ?

a) 5.00 in a direction 56.3° counterclockwise from the positive x axis

b) 6.72 in a direction 34.4° counterclockwise from the positive x-axis

c) 3.61 in a direction 33.7° counterclockwise from the positive x-axis

d) 3.61 in a direction −56.3° counterclockwise from the positive x-axis

e) 3.61 in a direction 56.3° counterclockwise from the positive x-axis

c) 117°

Determine the angle between the directions of vector (→A)=3.00ˆi+1.00ˆj and vector (→B)=−3.00ˆi+3.00ˆj.

a) 30.0°

b) 26.6°

c) 117°

d) 88.1°

e) 45.2°

b) Its acceleration is positive but its velocity is negative.

Suppose that a car traveling to the west (the −x direction) begins to slow down as it approaches a traffic light. Which statement concerning its acceleration in the x direction is correct?

a) Both its acceleration and its velocity are negative.

b) Its acceleration is positive but its velocity is negative.

c) Both its acceleration and its velocity are positive.

d) Its acceleration is negative but its velocity is positive

b) The acceleration is downward during the entire time the ball is in the air.

A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct?

a) The acceleration of the ball is downward while it is traveling up and upward while it is traveling down.

b) The acceleration is downward during the entire time the ball is in the air.

c) The acceleration of the ball is upward while it is traveling up and downward while it is traveling down.

d) The acceleration of the ball is downward while it is traveling up and downward while it is traveling down but is zero at the highest point when the ball stops.

a) remains constant.

Two objects are dropped from a bridge, an interval of 1.0 s apart, and experience no appreciable air resistance. As time progresses, the DIFFERENCE in their speeds

a) remains constant.

b) increases at first, but then stays constant.

c) decreases at first, but then stays constant.

d) decreases.

e) increases.

b) 1.3 h

If the fastest you can safely drive is 65 mi/h, what is the longest time you can stop for dinner if you must travel 541 mi in 9.6 h total?

a) You can't stop at all.

b) 1.3 h

c) 1.4 h

e) 1.0 h

c) 2.1 m/s

The position of an object as a function of time is given by x=bt^2−ct, where b=2.0m/s^2 and c=6.7m/s, and x and t are in SI units. What is the instantaneous velocity of the object when t=2.2?

a) 1.7 m/s

b) 2.3 m/s

c) 2.1 m/s

d) 2.7 m/s

d) 13m/s^2

The position of an object is given by x=at^3−bt^2+ct, where a=4.1m/s^3, b=2.2m/s^2, c=1.7m/s, and x and t are in SI units. What is the instantaneous acceleration of the object when t=0.7s?

a) 4.6m/s^2

b) 2.9m/s^2

c) −13m/s^2

d) 13m/s^2

b) 54.0 m/s

The acceleration of an object as a function of time is given by a(t)=(3.00m/s^3)t, where t is in seconds. If the object is at rest at time t=0.00s, what is the velocity of the object at time t=6.00s?

a) 18.0 m/s

b) 54.0 m/s

c) 0.00 m/s

d) 108 m/s

e) 15.0 m/s

a) 27.0 m

The acceleration of an object as a function of time is given by a(t)=(3.00m/s^3)t, where t is in seconds. If the object has a velocity 1.00m/s at time t=1.00s, what is the displacement of the object between time t=2.00s and time t=4.00s?

a) 27.0 m

b) 33.0 m

c) 36.0 m

d) 30.0 m

a) 133 m

A car accelerates from 10.0m/s to 30.0m/s at a rate of 3.00m/s^2. How far does the car travel while accelerating?

a) 133 m

b) 226 m

c) 80.0 m

d) 399 m

b) 4.15 m/s

A ball rolls across a floor with an acceleration of 0.100m/s^2 in a direction opposite to its velocity. The ball has a velocity of 4.00m/s after rolling a distance 6.00m across the floor. What was the initial speed of the ball?

a) 5.21 m/s

b) 4.15 m/s

c) 5.85 m/s

d) 4.60 m/s

e) 3.85 m/s

a) 9.4 s.

A ball is projected upward at time t=0.0s, from a point on a roof 90 m above the ground. The ball rises, then falls and strikes the ground. The initial velocity of the ball is 36.2 m/s if air resistance is negligible. The time when the ball strikes the ground is closest to

a) 9.4 s.

b) 8.7 s.

c) 9.0 s.

d) 10 s.

e) 9.7 s.

a) hA/hB=1/4

Two identical objects A and B fall from rest from different heights to the ground and feel no appreciable air resistance. If object B takes TWICE as long as object A to reach the ground, what is the ratio of the heights from which A and B fell?

a) hA/hB=1/4

b) hA/hB=1/√2

c) hA/hB=1/8

d) hA/hB=1/2

a) 487 m

A test rocket is fired straight up from rest with a net acceleration of 20.0m/s^2. After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach?

a) 487 m

b) 320 m

c) 408 m

d) 327 m

e) 160 m

b) g/2

On the earth, when an astronaut throws a 0.250-kg stone vertically upward, it returns to his hand a time T later. On planet X he finds that, under the same circumstances, the stone returns to his hand in 2T. In both cases, he throws the stone with the same initial velocity and it feels negligible air resistance. The acceleration due to gravity on planet X (in terms of g) is

a) g/4

b) g/2

c) g/√(2)

d) g√(2)

e) 2g

e) t√(2)

Two identical stones are dropped from rest and feel no air resistance as they fall. Stone A is dropped from height h, and stone B is dropped from height 2h. If stone A takes time t to reach the ground, stone B will take time

a) t/√(2)

b) t/2

c) 4t

d) 2t

e) t√(2)

c) the horizontal component of its velocity remains constant and the vertical component of its acceleration is equal to −g.

While an object is in projectile motion (with upward being positive) with no air resistance,

a) the horizontal component of its velocity remains constant and the horizontal component of its acceleration is equal to −g.

b) the horizontal component of its velocity remains constant and the vertical component of its acceleration is equal to zero.

c) the horizontal component of its velocity remains constant and the vertical component of its acceleration is equal to −g.

d) the vertical component of both its velocity and its acceleration remain constant.

e) the vertical component of its velocity remains constant and the vertical component of its acceleration is equal to −g.

b) the speed of Alice is larger than that of Tom.

Alice and Tom dive from an overhang into the lake below. Tom simply drops straight down from the edge, but Alice takes a running start and jumps with an initial horizontal velocity of 25 m/s. Neither person experiences any significant air resistance. Just as they reach the lake below,

a) they will both have the same speed.

b) the speed of Alice is larger than that of Tom.

c) the speed of Alice will always be 25 m/s larger than that of Tom.

d) the speed of Tom will always be 9.8 m/s larger than that of Alice.

e) the splashdown speed of Alice is larger than that of Tom.

c) They hit at the same time.

Jan and Len throw identical rocks off a tall building at the same time. The ground near the building is flat. Jan throws her rock straight downward. Len throws his rock downward and outward such that the angle between the initial velocity of the rock and the horizon is 30°. Len throws the rock with a speed twice that of Jan's rock. If air resistance is negligible, which rock hits the ground first?

a) Jan's rock hits first.

b) Len's rock hits first.

c) They hit at the same time.

d) It is impossible to know from the information given.

a) He should aim it at the monkey.

A monkey is sitting at the top of a tree 20 m above ground level. A person standing on the ground wants to feed the monkey. He uses a bow and arrow to launch the food to the monkey. If the person knows that the monkey is going to drop from the tree at the same instant that the person launches the food, how should the person aim the arrow containing the food? Air resistance is small enough to be ignored.

a) He should aim it at the monkey.

b) He should aim it below the monkey.

c) He should aim it above the monkey.

b) be over the package.

A pilot drops a package from a plane flying horizontally at a constant speed. Neglecting air resistance, when the package hits the ground the horizontal location of the plane will

a) be behind the package.

b) be over the package.

c) depend of the speed of the plane when the package was released.

d) be in front of the package.

True

True or false - For an object in uniform circular motion, its velocity and acceleration vectors are always perpendicular to each other at every point in the path.

e) larger in magnitude the smaller the radius of the circle

If an object travels at a constant speed in a circular path, the acceleration of the object is

a) zero.

b) smaller in magnitude the smaller the radius of the circle.

c) in the opposite direction of the velocity of the object.

d) in the same direction as the velocity of the object.

e) larger in magnitude the smaller the radius of the circle

a) 9.43 m/s

An object has a position given by(→r)=[2.0m+(5.00m/s)t]ˆi+[3.0m−(2.00m/s^2)t^2]ˆjwhere quantities are in SI units. What is the speed of the object at time t=2.00s?

a) 9.43 m/s

b) 6.40 m/s

c) 7.00 m/s

d) 7.65 m/s

e) 13.0 m/s

b) 0.110 s

A boy throws a rock with an initial velocity of 2.15m/s at 30.0° above the horizontal. If air resistance is negligible, how long does it take for the rock to reach the maximum height of its trajectory?

a) 0.215 s

b) 0.110 s

c) 0.303 s

d) 0.194 s

d) 27.3 m

A rock is thrown at a window that is located 18.0m above the ground. The rock is thrown at an angle of 40.0° above horizontal. The rock is thrown from a height of 2.00m above the ground with a speed of 30.0m/s and experiences no appreciable air resistance. If the rock strikes the window on its upward trajectory, from what horizontal distance from the window was it released?

a) 29.8 m

b) 71.6 m

c) 48.7 m

d) 27.3 m

e) 53.2 m

c) 574 m

A rescue plane flying horizontally at 72.6m/s spots a survivor in the ocean 182m directly below and releases an emergency kit with a parachute. Because of the shape of the parachute, it experiences insignificant horizontal air resistance. If the kit descends with a constant vertical acceleration of 5.82m/s^2, how far away from the survivor will it hit the waves?

a) 406 m

b) 4.54 km

c) 574 m

d) 602 m

e) 4.78°east of north

An airplane flies between two points on the ground that are 500 km apart. The destination is directly north of the origination of the flight. The plane flies with an air speed of 120 m/s. If a constant wind blows at 10.0 m/s due west during the flight, what direction must the plane fly relative to north to arrive at the destination?

a) 4.78°west of north

b) 4.76°west of north

c) 85.2°west of north

d) 4.76°east of north

e) 4.78°east of north

d) 157 m/s at an angle 7.31° south of east.

A plane has an eastward heading at a speed of 156 m/s (relative to the air). A 20.0 m/s wind is blowing southward while the plane is flying. The velocity of the plane relative to the ground is

a) 157 m/s at an angle 7.31° east of south.

b) 155 m/s at an angle 7.36° south of east.

c) 155 m/s at an angle 7.36° east of south.

d) 157 m/s at an angle 7.31° south of east.

e) 157 m/s at an angle 7.36° south of east.

b) 25.3 m/s at 82.4° from initial direction of motion

A small boat is moving at a velocity of 3.35m/s when it is accelerated by a river current perpendicular to the initial direction of motion. If the acceleration of the current is 0.750m/s2, what will be the new velocity of the boat after 33.5s?

a) 25.3 m/s at 7.59° from initial direction of motion

b) 25.3 m/s at 82.4° from initial direction of motion

c) 640.1 m/s at 82.4° from initial direction of motion

d) 640.1 m/s at 7.59° from initial direction of motion

a) 1.3 m/s

You want to swim straight across a river that is 76m wide. You find that you can do this if you swim at an angle of θ=28° from the upstream direction at a constant rate of 1.5m/s relative to the water. At what rate does the river flow? The angle θ is measured from the river bank (directly upstream is θ=0° while directly across the river is θ=90°).

a) 1.3 m/s

b) 0.70 m/s

c) 1.8 m/s

d) 1.6 m/s

a) 530 mi/h

A plane flies directly between two cities, A and B, which are separated by 2300 mi. From A to B, the plane flies into a 65 mi/h headwind. On the return trip from B to A, the wind velocity is unchanged. The trip from B to A takes 65 min less than the trip from A to B. What is the airspeed of the plane, assuming it is the same in both directions?

a) 530 mi/h

b) 610 mi/h

c) 400 mi/h

d) 480 mi/h

a) 2403m/s^2

An electrical motor spins at a constant 2857.0 rev/min. If the armature radius is 2.685 cm, what is the acceleration of the outer edge of the armature?

a) 2403m/s^2

b) 241,100m/s^2

c) 844.4m/s^2

d) 84.40m/s^2

c) rA/rB=2.1.

Two particles, A and B, are in uniform circular motion about a common center. The acceleration of particle A is 8.5 times that of particle B. The period of particle B is 2.0 times the period of particle A. The ratio of the radius of the motion of particle A to that of particle B is closest to

a) rA/rB=4.3.

b) rA/rB=17.

c) rA/rB=2.1.

d) rA/rB=18.

e) rA/rB=0.24.

e) exactly 1500 N whether or not the box moves.

You swing a bat and hit a heavy box with a force of 1500 N. The force the box exerts on the bat is

a) greater than 1500 N if the bat bounces back.

b) greater than 1500 N if the box moves.

c) less than 1500 N if the box moves.

d) exactly 1500 N only if the box does not move.

e) exactly 1500 N whether or not the box moves.

a) zero.

A stalled car is being pushed up a hill at constant velocity by three people. The net force on the car is

a) zero.

b) up the hill and greater than the weight of the car.

c) up the hill and equal to the weight of the car.

d) down the hill and equal to the weight of the car.

e) down the hill and greater than the weight of the car

False

True or False - In order to lift a bucket of concrete, you must pull up harder on the bucket than it pulls down on you.

c) T>ma.

A box of mass m is pulled with a constant acceleration a along a horizontal frictionless floor by a wire that makes an angle of 15° above the horizontal. If T is the tension in this wire, then

a) Tma.

b) No forces were acting on you to cause you to fall.

You are standing in a moving bus, facing forward, and you suddenly fall forward as the bus comes to an immediate stop. The force acting on you that causes you to fall forward is

a) the force due to kinetic friction between you and the floor of the bus.

b) No forces were acting on you to cause you to fall.

c) the force due to static friction between you and the floor of the bus.

d) the force of gravity.

e) the normal force due to your contact with the floor of the bus.

c) When you push down on the earth with a force greater than your weight, the earth will push back with the same magnitude force and thus propel you into the air.

Consider what happens when you jump up in the air. Which of the following is the most accurate statement?

a) Since the ground is stationary, it cannot exert the upward force necessary to propel you into the air. Instead, it is the internal forces of your muscles acting on your body itself that propels your body into the air.

b) You are able to spring up because the earth exerts a force upward on you that is greater than the downward force you exert on the earth.

c) When you push down on the earth with a force greater than your weight, the earth will push back with the same magnitude force and thus propel you into the air.

d) It is the upward force exerted by the ground that pushes you up, but this force cannot exceed your weight.

e) When you jump up the earth exerts a force F1 on you and you exert a force F2 on the earth. You go up because.F1>F2.

a) the force of on the truck due to the collision is exactly equal to the force on the car.

A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the car. During the collision

a) the force of on the truck due to the collision is exactly equal to the force on the car.

b) the car and the truck have the same magnitude acceleration.

c) the force on the car due to the collision is much greater than the force on the truck.

d) the force on the truck due to the collision is slightly greater than the force on the car

a) The net force on the object is zero.

An object is moving forward with a constant velocity. Which statement about this object MUST be true?

a) The net force on the object is zero.

b) The acceleration of the object is in the forward direction.

c) No forces are acting on the object.

d) The net force on the object is in the forward direction.

b) the velocity is zero, the acceleration is directed downward, and the force of gravity acting on the ball is directed downward.

A ball is tossed vertically upward. When it reaches its highest point (before falling back downward)

a) the velocity is zero, the acceleration is zero, and the force of gravity acting on the ball is zero.

b) the velocity is zero, the acceleration is directed downward, and the force of gravity acting on the ball is directed downward.

c) the velocity, acceleration, and the force of gravity on the ball all reverse direction.

d) the velocity and acceleration reverse direction, but the force of gravity on the ball remains downward.

e) the velocity is zero, the acceleration is zero, and the force of gravity acting on the ball is directed downward.

c) You cannot conclude anything about the direction of the velocity of the bus.

You are seated in a bus and notice that a hand strap that is hanging from the ceiling hangs away from the vertical in the backward direction. From this observation, you can conclude that

a) the velocity of the bus is forward.

b) the velocity of the bus is backward.

c) You cannot conclude anything about the direction of the velocity of the bus.

e) 224 N in a direction 26.6° north of west

The following four forces act on a 4.00 kg object:

→F1=300Neast

→F2=700Nnorth

→F3=500Nwest

→F4=600Nsouth

What is the acceleration of the object?

a) 300 N in a direction 63.4° north of west

b) 300 N in a direction 26.6° north of west

c) 224 N in a direction 63.4° north of west

d) 2100 N in a direction 26.6° north of west

e) 224 N in a direction 26.6° north of west

c) The worker will accelerate at 2.17m/s^2 and the box will accelerate at 1.08m/s2, but in opposite directions.

On a horizontal frictionless floor, a worker of weight 0.900 kN pushes horizontally with a force of 0.200 kN on a box weighing 1.80 kN. As a result of this push, which statement could be true?

a) The worker and box will both have an acceleration of 2.17m/s^2, but in opposite directions.

b) The box will not move because the push is less than its weight.

c) The worker will accelerate at 2.17m/s^2 and the box will accelerate at 1.08m/s^2, but in opposite directions.

d) The worker will accelerate at 1.08m/s^2 and the box will accelerate at 2.17m/s^2, but in opposite directions.

e) The worker and box will both have an acceleration of 1.08m/s^2, but in opposite directions.

c) 77 N

A block is on a frictionless horizontal table, on earth. This block accelerates at 1.9m/s^2 when a 90N horizontal force is applied to it. The block and table are then set up on the moon where the acceleration due to gravity is 1.62m/s^2. What is the weight of the block on the moon?

a) 39 N

b) 58 N

c) 77 N

d) 67 N

e) 48 N

d) 118,000 N.

A 10,000-kg rocket blasts off from earth with a uniform upward acceleration of 2.00m/s^2 and feels no air resistance. The upward thrust force its engines must provide during this acceleration is closest to

a) 20,000 N.

b) 78,000 N.

c) 980,000 N.

d) 118,000 N.

b) 1.6×10^4N

Bumpers on cars are not of much use in a collision. To see why, calculate the average force a bumper would have to exert if it brought a 1200-kg car (a so-called compact model) to a rest in 15 cm when the car had an initial speed of 2.0 m/s (about 4.5 mph). (Bumpers are built with springs that compress to provide a stopping force without, hopefully, denting the metal.)

a) 6.5×10^5N

b) 1.6×10^4N

c) 1.8×10^4N

d) 3.2×10^4N

e) 5.4×10^4N

c) You cannot tell if it is moving upward or downward.

A 615 N student standing on a scale in an elevator notices that the scale reads 645 N. From this information, the student knows that the elevator must be moving

a) downward.

b) upward.

c) You cannot tell if it is moving upward or downward.

e) The two objects reach the bottom of the incline at the same time.

Two objects have masses m and 5m, respectively. They both are placed side by side on a frictionless inclined plane and allowed to slide down from rest.

a) It takes the heavier object 10 times longer to reach the bottom of the incline than the lighter object.

b) It takes the heavier object 5 times longer to reach the bottom of the incline than the lighter object.

c) It takes the lighter object 10 times longer to reach the bottom of the incline than the heavier object.

d) It takes the lighter object 5 times longer to reach the bottom of the incline than the heavier object.

e) The two objects reach the bottom of the incline at the same time.

a) tension and gravity

A string is attached to the rear-view mirror of a car. A ball is hanging at the other end of the string. The car is driving around in a circle, at a constant speed. Which of the following lists gives all of the forces directly acting on the ball?

a) tension and gravity

b) tension

c) tension, gravity, and the centripetal force

d) tension, gravity, the centripetal force, and friction

b) right after the object is released.

Suppose the force of the air drag on an object is proportional to the speed of the object and in the direction opposite the object's velocity. If you throw an object upward, the magnitude of its acceleration is greatest

a) at the top of its trajectory.

b) right after the object is released.

c) The acceleration of the object is the same throughout the entire trajectory.

a) 59 kg

You push downward on a box at an angle 25° below the horizontal with a force of 750 N. If the box is on a flat horizontal surface for which the coefficient of static friction with the box is 0.76, what is the mass of the heaviest box you will be able to move?

a) 59 kg

b) 82 kg

c) 68 kg

d) 54 kg

b) 4.7m/s^2

A 6.0 kg box slides down an inclined plane that makes an angle of 39° with the horizontal. If the coefficient of kinetic friction is 0.19, at what rate does the box accelerate down the slope?

a) 5.5m/s^2

b) 4.7m/s^2

c) 5.2m/s^2

d) 6.2m/s^2

b) 42.0 m/s

A car enters a 300-m radius horizontal curve on a rainy day when the coefficient of static friction between its tires and the road is 0.600. What is the maximum speed at which the car can travel around this curve without sliding?

a) 24.8 m/s

b) 42.0 m/s

c) 29.6 m/s

d) 37.9 m/s

e) 33.1 m/s

a) 23.9°

Question 8:Engineers are designing a curved section of a highway. If the radius of curvature of the curve is 194 m, at what angle should the curve be banked so that a car traveling at 29.0 m/s will stay on the road without the aid of frictional forces?

a) 23.9°

b) 21.0°

c) 16.7°

d) 26.1°

b) 11.4 m/s

A new roller coaster contains a loop-the-loop in which the car and rider are completely upside down. If the radius of the loop is 13.2 m, with what minimum speed must the car traverse the loop so that the rider does not fall out while upside down at the top? Assume the rider is not strapped to the car.

a) 10.1 m/s

b) 11.4 m/s

c) 14.9 m/s

d) 12.5 m/s

d) 12.6 m/s

An 80.0-kg object is falling and experiences a drag force due to air resistance. The magnitude of this drag force depends on its speed, v, and obeys the equation Fdrag=(12.0N⋅s/m)v+(4.00N⋅s^2/m^2)v^2. What is the terminal speed of this object?

a) 47.3 m/s

b) 72.2 m/s

c) 6.45 m/s

d) 12.6 m/s

e) 34.2 m/s

c) (1) and (2)

A stock person at the local grocery store has a job consisting of the following five segments: (1) picking up boxes of tomatoes from the stockroom floor (2) accelerating to a comfortable speed (3) carrying the boxes to the tomato display at constant speed (4) decelerating to a stop (5) lowering the boxes slowly to the floor. During which of the five segments of the job does the stock person do positive work on the boxes?

a) (1) only

b) (1), (2), (4), and (5)

c) (1) and (2)

d) (2) and (3)

e) (1) and (5)

a) the reciprocal of the spring constant.

Consider a plot of the displacement (x) as a function of the applied force (F) for an ideal elastic spring. The slope of the curve would be

a) the reciprocal of the spring constant.

b) the mass of the object attached to the spring.

c) the acceleration due to gravity.

d) the reciprocal of the acceleration of gravity.

e) the spring constant.

True

True or false - If a force always acts perpendicular to an object's direction of motion, that force cannot change the object's kinetic energy.

b) the heavier one will have twice the kinetic energy of the lighter one.

Two objects, one of mass m and the other of mass 2m, are dropped from the top of a building. When they hit the ground

a) both of them will have the same kinetic energy.

b) the heavier one will have twice the kinetic energy of the lighter one.

c) the heavier one will have four times the kinetic energy of the lighter one.

d) the heavier one will have √2 times the kinetic energy of the lighter one.

c) 0.0 J

You carry a 7.0 kg bag of groceries 1.2 m above the level floor at a constant velocity of 75 cm/s across a room that is 2.3 m room. How much work do you do on the bag in the process?

a) 82 J

b) 158 J

c) 0.0 J

d) 134 J

d) -330 J

Find the net work done by friction on the body of a snake slithering in a complete circle of 3.93 m radius. The coefficient of friction between the ground and the snake is 0.25, and the snake's weight is 54.0 N.

a) -670 J

b) -3300 J

c) 0 J

d) -330 J

b) 75 N

A traveler pulls on a suitcase strap at an angle 36° above the horizontal. If 908 J of work are done by the strap while moving the suitcase a horizontal distance of 15 m, what is the tension in the strap?

a) 92 N

b) 75 N

c) 61 N

d) 85 N

b) 46 J

A force (→F)=12Nˆi−10Nˆj acts on an object. How much work does this force do as the object moves from the origin to the point (→r)=13mˆi+11mˆj

a) 37 J

b) 46 J

c) 266 J

d) 62 J

a) 619 J

A person pushes horizontally on a heavy box and slides it across the level floor at constant velocity. The person pushes with a 60.0 N force for the first 6.88 m, at which time he begins to tire. The force he exerts then starts to decrease linearly from 60.0 N to 0.00 N across the remaining 6.88 m. How much total work did the person do on the box?

a) 619 J

b) 826 J

c) 495 J

d) 925 J

a) 45 km/h

A 1000.0 kg car is moving at 15 km/h. If a 2000.0 kg truck has 18 times the kinetic energy of the car, how fast is the truck moving?

a) 45 km/h

b) 63 km/h

36 km/h

54 km/h

b) 4.08 kJ

A worker lifts a 20.0-kg bucket of concrete from the ground up to the top of a 20.0-m tall building. The bucket is initially at rest, but is traveling at 4.0 m/s when it reaches the top of the building. What is the minimum amount of work that the worker did in lifting the bucket?

a) 160 J

b) 4.08 kJ

c) 3.92 kJ

d) 560 J

e) 400 J

a) the sled's speed will be v√2 and its kinetic energy will be 2K.

A constant horizontal pull acts on a sled on a horizontal frictionless ice pond. The sled starts from rest. When the pull acts over a distance x, the sled acquires a speed v and a kinetic energy K. If the same pull instead acts over twice this distance,

a) the sled's speed will be v√2 and its kinetic energy will be 2K.

b) the sled's speed will be 2v and its kinetic energy will be K√2.

c) the sled's speed will be v√2 and its kinetic energy will be K√2.

d) the sled's speed will be 2v and its kinetic energy will be 2K.

e) the sled's speed will be 4v and its kinetic energy will be 2K.

c) It would have skidded 4 times farther.

You slam on the brakes of your car in a panic, and skid a certain distance on a straight, level road. If you had been traveling twice as fast, what distance would the car have skidded, under identical conditions?

a) It would have skidded 2 times farther.

b) It would have skidded √2 times farther.

c) It would have skidded 4 times farther.

d) It would have skidded 1/√2 times farther.

e) It would have skidded 1/2 as far.

b) 18 W

A child pulls on a wagon with a horizontal force of 75 N. If the wagon moves horizontally a total of 42 m in 3.0 min, what is the average power generated by the child?

a) 22 W

b) 18 W

c) 27 W

d) 24 W

b) 20.9s

How long will it take a 7.08hp motor to lift a 250kg beam directly upward at constant velocity from the ground to a height of 45.0m? Assume frictional forces are negligible. (1hp=746W)

a) 1.56×10^4s

b) 20.9s

c) 2.18×10^4s

d) 39.7s

c) $0.81

If electricity costs 6.00¢/kWh (kilowatt-hour), how much would it cost you to run a 120 W stereo system 4.0 hours per day for 4.0 weeks?

a) $0.12

b) $1.38

c) $0.81

d) $2.27

c) Yes, since the choice of the zero of potential energy is arbitrary.

Is it possible for a system to have negative potential energy?

a) Yes, as long as the kinetic energy is positive.

b) No, because this would have no physical meaning.

c) Yes, since the choice of the zero of potential energy is arbitrary.

d) No, because the kinetic energy of a system must equal its potential energy.

e) Yes, as long as the total energy is positive.

a) At its highest point, the heavier stone will have twice as much gravitational potential energy as the lighter one because it is twice as heavy.

Two stones, one of mass m and the other of mass 2m, are thrown directly upward with the same velocity at the same time from ground level and feel no air resistance. Which statement about these stones is true?

a) At its highest point, the heavier stone will have twice as much gravitational potential energy as the lighter one because it is twice as heavy.

b) At their highest point, both stones will have the same gravitational potential energy because they reach the same height.

c) Both stones will reach the same height because they initially had the same amount of kinetic energy.

d) The heavier stone will go twice as high as the lighter one because it initially had twice as much kinetic energy.

e) The lighter stone will reach its maximum height sooner than the heavier one.

c) Ball B will go four times as high as ball A because it had four times the initial kinetic energy.

Two identical balls are thrown directly upward, ball A at speed v and ball B at speed 2v, and they feel no air resistance. Which statement about these balls is correct?

a) At their highest point, the acceleration of each ball is instantaneously equal to zero because they stop for an instant.

b) The balls will reach the same height because they have the same mass and the same acceleration.

c) Ball B will go four times as high as ball A because it had four times the initial kinetic energy.

d) At its highest point, ball B will have twice as much gravitational potential energy as ball A because it started out moving twice as fast.

e) Ball B will go twice as high as ball A because it had twice the initial speed.

True

True or false - When an object is solely under the influence of conservative forces, the sum of its kinetic and potential energies does not change.

b) less than 30 J

A ball drops some distance and loses 30 J of gravitational potential energy. Do NOT ignore air resistance. How much kinetic energy did the ball gain?

a) exactly 30 J

b) less than 30 J

c) more than 30 J

b) The force is identical on the two systems.

A potential energy function for system 1 is given by U1(x)=Cx^2+Bx^3. The potential energy function for system 2 is given by U2(x)=A+Cx^2+Bx^3, where A is a positive quantity. How does the force on system 1 relate to the force on system 2 at a given position?

a) The force on the second system will be with greater than the force on the first system.

b) The force is identical on the two systems.

c) The force on the two systems will be in opposite directions.

d) There is no relationship between the forces on the two systems.

e) The force on the second system will be with less than the force on the first system.

b) 110 cm

A tennis ball bounces on the floor three times. If each time it loses 22.0% of its energy due to heating, how high does it rise after the third bounce, provided we released it 2.3 m from the floor?

a) 110 mm

b) 110 cm

c) 140 cm

d) 11 cm