cp physics roz chapts 1-6 midterm review

The study of the fundamental laws of nature

Physics

In the quotient A/(BxC), A has 5 significant figures, B has 2 significant figures, and C has 3 significant figures. How many significant figures does the quotient have?

2

Express 50 mi/h in units of meters per second (1 mi=1609m)

22 m/s

How many significant figures are in the number 120.070?

six

In the product AxBxC, A has 5 significant figures, B has 2 significant figures, and C has 3 significant figures. How many significant figures does the product have?

2

A detailed explanation of some aspect of nature that accounts for a set of well-tested hypotheses

Theory

The variable that is changed in an experiment

independent variable

What is 0.674/0.74 expressed to the correct number of significant figures?

0.91

The metric system is preferred over the British system in science for the following main reason

Conversations between metric quantities are especially easy because they are all related by factors of ten

When multiplying several quantities

The quantities can have any combination of units

In Einstein's famous equation E=mc62, describing the relationship between matter and energy, E stands for energy, m stands for mass, and c is the speed of light in vacuum. What are the SI units of E?

Kg x m^2/s^2

In the difference A - B - C, A is accurate to 5 decimal places, B is accurate to 2 decimal places, and C is accurate to 3 decimal places. What is the correct number of decimal places in the difference?

2

Which of the following numbers is the smallest

15 x 10^3

The systematic approach scientists use to learn about the laws of nature?

Scientific Method

Which one of the following numbers is equivalent to the number 0.0001776

1.776 x 10^-4

A measure of the gravitational force acting on an object

Weight

The digits actually measured plus one estimated digit in a properly expressed measurement

Significant figures

A preference for a particular point of view due to personal rather than scientific reasons

Bias

In the sum A + B + C, A is accurate to 5 decimal places, B is accurate to 2 decimal places, and C is accurate to 3 decimal places. What is the correct number of decimal places in the sum?

2

What is the product of 12.56 and 2.12 expressed to the correct number of significant figures?

26.6

A measure of the amount of matter in an object?

Mass

A quantity consisting of both a numerical with its unit and a direction

Vector

The number 0.00325 x 10^-8cm can be expressed in millimeters as

3.25 x 10^-10mm

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 of the rectangle should be written as?

0.682 m^2

What is the sum of 2.67 + 1.976 +2.1 expressed to the correct number of significant figures

6.7

Express the number 13.5 gigameters in meters without using scientific notation

13,500,000,000 m

When adding several quantities

The quantities must all have exactly the same units

Add 1299g and 45.1 kg and express your answer in milligrams (mg) to the correct number of significant figures

4.64 x 10^7

How many significant figures are in the number 0.0037010/

five

A detailed explanation for a set of observations that can be verified or rejected by careful experiments

Hypothesis

In a chosen coordinate system, the time interval of an object in motion can have a negative value.

False

The slope of a position-time graph of an object gives the speed of the object.

False

If a drag racer wins the final round of her race by going an average speed of 198.37 miles per hour in 4.537 seconds, what distance did she cover?

0.2500 miles

Scalar measurements have both magnitude and direction

False

Which of the following is a pair of scalar quantities

Time and speed

A time interval is a scalar quantity

true

The magnitude of a displacement vector represents the

distance

The final position minus the initial position is the

displacement

The average velocity is defined as the ratio of the change of position to the time interval during which the change occurred

true

The y-intercept of a position-time graph of an object gives the average velocity of the object

false

A car is moving with a uniform speed of 15.0 m/s along a straight path. What is the distance covered by the car in 12.0 minutes

1.09 x 101km

Joe and Sadie are supposed to meet at 3 pm in Springfield, which is 150 km away from where they love. Joe leaves home at noon, traveling 50 km.her. True or False: If Sadie leaves home at 1:30 pm and travels at 75 km/hr, she will meet Joe in Springfield on time

False

In a chose coordinate system, the position of an object in motion can have negative values

True

The final time minus the initial time equals the

time interval

The absolute value of the average velocity is the average

speed

Given below is the graph representing the potion-time grapes of 2 swimmers (A and B), swimming in a pool along a straight line. Both the swimmers start from two different positions. Using the graph when and where does swimmer B pass swimmer A?

Time = 38 seconds, position = 150 meters

The position-time graph below represents the motion of Ted returning home from the market on his bike. WHat is Ted's displacement during the time interval from t = 1 second to t = 3 seconds?

- 10 meters

In a coordinate system, the point at which both variables have a value of zero i called the

Origin

Which of the following is a pair of vector quantities?

Velocity and displacement

A collision between two moving objects can be represented on a position-time graph

True

The position-time graph of an object moving with a constant average velocity is always a straight line.

True

The SI units of acceleration are

m/s^2

What is true of the terms acceleration and acceleration

Negative acceleration is always acceleration in the negative direction; An object can decelerate even when its velocity is in the positive direction; Deceleration occurs only when the acceleration is opposite in direction to the velocity

Acceleration occurs when an object undergoes

change in both speed and direction; change in speed; change in direction

Near the surface of the Earth, in the absence of air resistance, all objects will experience approximately the same acceleration due

true

While the human body cannot detect acceleration, it can sense constant velocity

false

The position-time equation matching this position-time graph is

Df = di + vit+1/2at(2)

The slope of the tangent to the curve on this velocity- time graph is equal to___at this point

Instantaneous acceleration

A car accelerates from 20.0 m/s to 26.8 m/s in 3.2 s. Whats the cars average acceleration?

2.1 m/s (2)

A drag racer accelerates from rest at 7.5m/s(2). How far will it travel in 8.0s

240cm

A ball is dropped from rest at a height of 3.0m. How much time does it take to hit the ground

0.78s

A ball is dropped from rest and takes 4.0s to reach the ground. What is its final speed and instant before hitting the ground?

160m/s

How far does a ball that is dropped from rest fall 3.0s

44m

Distance, mass, time, and temperature are examples of ______ quantities

scalar

A quantity that has both magnitude and direction is a _____ quantity

vector

If 2 vectors have directions that are at right angles to each other, the magnitude of the sum of the 2 vectors can be found using the Pythagorean theorem.

true

What is true of adding vectors graphically?

The resultant vector R is the vector from the tail of the first vector to the tip of the last vector added

You drop a ball straight down, and at the same instant and from the same height you throw another ball sideways (i.e., with horizontal velocity only). If we ignore air resistance, which of these statements is true?

Both balls fall with the same acceleration n the vertical direction; Neither ball has acceleration in the horizontal direction; Both balls hit the ground at the same time

You are driving in a straight line at 5 mph on your motorbike, and you drop a baseball from your right hand that is extended to your right side. If we can ignore wind and air resistance, the ball hits the ground directly below the spot where your hand was back when it let go of the ball.

false

When adding vectors by components using trigonometric functions, the x component of the resultant is the sum of the x component of the added vectors, and the y component of the resultant is the sum of the y components of the added vectors.

true

A launched projectile is moving in two dimensions under the influence of gravity's downward acceleration and we are able to ignore air resistance. The projectile's path is

parabolic

A projectile's motion can be understood by analyzing the horizontal and vertical motions independently.

true

What is the magnitude, V, of vector V?

5.1m

What is the direction, Ø, of vector V? (with respect to the positive x-axis)

60 degrees

V is a velocity vector of magnitude 12 m/s and at an angle of 36° below the positive x-axis. What are the vector's components Vx and Vy?

Vx = 9.7 m/s and Vy = -7.1 m/s

Determine the magnitude and direction of Vector R=A+B

R=17.1; ØR=42.2°

A football placekicker kicks the ball from the ground with a velocity of 180.0 m/s at an angle of 30.0° above the ground. If the ball hits the ground 28.7m down the field, what is the total time of flight of the ball? Ignore air resistance. (First determine the x-component of the ball's initial velocity)

1.84s

If a cannon has an initial velocity of 60.0 m/s and is fired at an angle of 35.0° above the horizontal and along level ground, what horizontal range does it achieve? Ignore air resistance.

345 m

At what angle of fire will the cannon ^ achieve its maximum range?

45 degrees

F=ma

Newton's Second Law

When a rocket exerts a force on the gases spewing out of its tail , the gases exert an equally strong opposite force back on the rocket, and propulsion of the rocket is achieved

Newtons third law

I drove my bike into a curb. The bike stopped but I flew forward

Newtons First Law

Newton's first law is often referred to as the law of

Inertia

The symbol means (the E)

sum

When an object sits on a surface and is subject to the downward force of gravity, it is also subject to an upward force exerted by and perpendicular to the surface called the

Normal force

Weight and Mass are essentially the same thing, both vary with the gravity of the planet you are on

False

A diagram that shows all force acting on an object is called

free body diagram

Which of the following statements is true?

The magnitude of the force of friction depends on (is proportional to) the normal force

In solving for the acceleration of an object is a E problem, we use the component of force acting in the same direction (x or y) as that acceleration

True

An 873-kg dragster, starting from rest, attains a speed of 26.3m/s in 7.75 m of travel. What is the net force on the dragster during this time? (Ignore friction)

3.9 x 10(4)N

A tow truck chain exerts a force of 2,620M to pull a 2,000-kg car. What acceleration does that give the car? (Ignore friction)

1.31m/s(2)

A book of mass 1.80kg rests on a table top. What is the normal force, Fn, of the table top on the book?

17.7

You use a rope to pull a sled with a force of 10.0N, with the rope at an angle of 30.0 degrees above the ground. With what effective horizontal force component are you pulling the sled forward along the ground?

8.66N

the joule is the SI unit for both work and energy

true

since work = Fd(cosin), when the force on an object and the displacement of the object are perpendicular to each other, no work is done on the object

true

in general, the ____energy of an energy of an object is energy due to motion

kinetic

Changes in gravitational potential energy depend only on the change in vertical height, and not the path taken

true

which of these statements about total mechanical energy is true?

all of these above

the faster a given amount of work is done, the greater the power is produced

true

an earth mover pushes a 425kg pile of stones horizonatally along a distance of 95m. How much work does the earth mover do if the pile is accelerated at 1.8m/s^2?

7.3 x 10^4 J