Physics Finbal Study Guide

Determine the accuracy (the number of significant digits) in 20,570 lb.

4

16 lb. = ______N

71

Determine the precision of the measurement: 0.0500 s.

.0001

When multiplying or dividing two or more measurements, the units

can be different.

For the following measurement, find the measurement that is the least precise: 208 m; 18050 m; 0.08 m; 0.750 m; 12.0 m.

18050 m

For the following measurement, find the measurement that is the least accurate: 208 m; 18050 m; 0.08 m; 0.750 m; 12.0 m.

0.08 m

Use the rule for addition of measurements to find the value of the following: 3847 m + 5800 m + 1230 m

10900 m

What are the basic metric units for length, mass, and time?

Meter, kilogram, second

When a value is multiplied or divided by 1, the value is

unchanged.

A rectangle has a perimeter of 40.0 cm. One side has a length of 14.0 cm. What is the length, in cm, of an adjacent side?

6.0

A rectangular plot of land measures 40.0 m by 120.0 m, with a parcel 10.0 m by 12.0 m out of one corner for an electrical transformer. What is the area, in meters squared, of the remaining plot?

4680

Given A = ½ bh, if b = 12.2 cm and h = 20.0 cm, what, in centimeters squared, is A?

122

A rectangle has a perimeter of 40.0 cm. One side has a length of 14.0 cm. What is the length, in cm, of an adjacent side?

6.0

Solve F = ma for a.

F/m

Solve F = ma for m.

F/a

Given A = π r², if A = 15.0 m², find r.

2.19 m

The formula for the area of a triangle is A = 1/2bh.  If b = 16.2 m, and A =98.6 m², find h.

12.2 m

Solve F = ma for a.

F/m

A sports car, starting from rest, accelerates to a speed of 60.0 mph in 6.00 seconds. What was the acceleration of the car, in ft/s^2, during the run?

14.7

A penny drops from the third floor (10.0 meters above the first floor) of the science building. Neglecting air resistance, how long, in seconds, was the coin in the air?

1.43

A sports car, starting from rest, accelerates to a speed of 60.0 mph in 6.00 seconds. Approximately how far, in feet, did the car travel during the run?

264

A runner starts from rest and attains a speed of 8.00 ft/s after 2.00 s. What is the runner’s acceleration?

4.00 ft/s²

A rock is dropped (initial speed is zero) from a bridge to the water below. It takes 2.40 s for the rock to hit the water. How high is the bridge above the water?

28.2 m

A rock is thrown straight down from a cliff with an initial velocity of 10.0 m/s.  Its final velocity when it strikes the water below is 115 m/s.  How long is the rock in flight?

10.7 s

A large heavy rock and a small marble are dropped at the same time from the roof of a two-story building. Neglecting air resistance, which object will strike the ground first?

They both strike the ground at the same time.

A rock is dropped (initial speed is zero) from a bridge to the water below. It takes 2.40 s for the rock to hit the water. How high is the bridge above the water?

28.2 m

An automobile accelerates from 55.0 km/h to 85.0 km/h in 8.70 s.  What is its acceleration in m/s²?  Recall 1 km = 1000 m, and 1h = 3600 s.

0.958 m/s²

At what launch angle with the ground does a projectile have the greatest horizontal range?

45⁰

A crate of mass 6.00 kg is moved by a force of 18.0 N. What is its acceleration in m/s^2?

3.00

Find the total force necessary, in N, to give a 280-kg motorcycle an acceleration of 3.20 m/s^2.

9.0 x 10^2

According to Newton’s second law, the law of acceleration,

force is equal to mass times acceleration.

A hammer weighs 12.5-N on Earth where the gravitational acceleration is 9.80 m/s².  What is its mass?

1.28 kg

Friction

always acts parallel to the surface of contact and opposite to the direction of motion.

The law of motion stating that objects at rest will remain at rest and objects in motion will remain in motion in a straight line with constant speed unless acted upon by some external force is known as

Newton's first law of motion.

Find the weight of a 125-kg cart on the earth.  The acceleration due to gravity on earth is g=9.80 m/sec².

1230 N

Given 1 lb. =4.45 N. The weight of a 10-lb bag of sugar is approximately

44.5 N

The law of motion stating that objects at rest will remain at rest and objects in motion will remain in motion in a straight line with constant speed unless acted upon by some external force is known as

Newton's first law of motion.

What force, in Newtons, is required to stop a 3001 kg truck going 35.0 km/h within 5.00 s?

5840

Find the weight, in pounds, of an automobile of traveling 88 ft/s with a momentum of 9680 slug ft/s.

3,500

A 125 kg pile driver hits a piling with a momentum of 1750 kg m/s. What was its speed, in m/s, as it hit the piling?

14.0

What force is required to stop a 2525 kg truck going 9.72 m/s in t =5.00 s?

4910 N

The impulse experienced by a body is equivalent to its change in:

momentum

A ball of mass 0.50 kg is thrown straight up at 6.0 m/s.  What is the momentum of the ball when it is at its peak?

0.0 kg m/s

A ball of mass 0.50 kg is thrown straight up at 6.0 m/s.  What is the momentum of the ball when it is at its peak?

0.0 kg m/s

A force of 30.0 N is applied to a shaft of radius 2.00 m. What is the torque, in N m, on the shaft?

60.0

A motorcycle head bolt is torqued to 25.0 N m. What length shaft, in meters, do we need on a wrench to exert a maximum force of 70.0 N?

.357

A torque of 175 lb ft is needed to free a large rusted on nut. The length of the wrench is 1.10 ft. What force, in pounds, must be applied to free it?

159

An automobile differential with a mass of 76.0 kg is 1.00 m from the end of a 2.22 m workbench. What mass, in kg, must each end of the workbench support?

34.2,41.8

The torque on a shaft of radius 2.00 cm is 12.0 N m. What force, in Newtons, is being applied to the shaft?

600

A force of 30.0 N is applied to a shaft of radius 2.00 m. What is the torque, in N m, on the shaft?

60.0

A motorcycle head bolt is torqued to 25.0 N m. What length shaft, in meters, do we need on a wrench to exert a maximum force of 70.0 N?

.357

A torque of 175 lb ft is needed to free a large rusted on nut. The length of the wrench is 1.10 ft. What force, in pounds, must be applied to free it?

159

The torque on a shaft of radius 2.00 cm is 12.0 N m. What force, in Newtons, is being applied to the shaft?

600

In the second condition of equilibrium,

clockwise and counterclockwise torques are equal.

Torque is

applied force times the length of the torque arm.

The study of an object in equilibrium is called

statics

The first condition of equilibrium states that

all parallel forces must be zero

A torque wrench reads 14.5 N m.  If its length is 25.0 cm, what force is being applied to the handle?

58.0 N

How much work, in lb ft, is required for a mechanical hoist to lift a 3500 lb automobile to a height of 7.0 feet for repairs?

25,000

An air gun fires a pellet with a mass of 0.0010 slugs. The slug is fired from the gun, and after which possesses of 720 lb ft of kinetic energy. Find its velocity, in ft/s.

1200

A wrecking ball of mass 11.4 kg is poised 22.0 m above home plate at Dodger Town. With respect to home plate, what is the potential energy, in Joules, of the wrecking ball?

2460

Work is done when

force is applied to an object and the object is moved

The quantity "mgh" is known as

potential energy

How much work is done in lifting 450 lb of cement 75 ft above the ground?

34000 ft lb

If the velocity of an object is doubled, by what factor is its kinetic energy increased?

4

The quantity ½ mv² is known as

kinetic energy

A girl and sled whose combined mass is 50.0 kg sit on top of an ice-covered hill which 25.0 m above sea level.  If we agree that their potential energy is zero at sea level. What would their potential energy be at the top of the hill? (The gravitational acceleration is 9.8 m/sec².)

12300 J

A golf cart with a mass of 8.0 slugs follows a curve of radius 56-ft with a speed of 12-ft/s. What is the centripetal force, in pounds, exerted by the golf cart as it is rounding a curve?

21

A golf cart with a mass of 8.0 slugs follows a curve of radius 56-ft with a speed of 12-ft/s. What is the centripetal force, in pounds, exerted by the golf cart as it is rounding a curve?

21

Convert 136 rpm to rad/s.

14.2

Find the power developed by an engine with a torque of 125 Nm applied at 195 rpm?  Recall rpm = revolution per minute, 1 revolution = 2π radians, and I minute = 60.0 second.

2550 W

The centripetal force on a runner is 45.0 lb.  If the runner has a mass of 5.50 slugs and his speed is 15.0 ft/s, find the radius of the curve.

27.5 ft

Find the power developed by an engine with a torque of 125 Nm applied at 195 rpm?  Recall rpm = revolution per minute, 1 revolution = 2π radians, and I minute = 60.0 second.

2550 W

A wheel of 1.00 m radius turns as 253 rpm.  Recall 1 revolution = 2π radius, and 1 minute = 60.0 seconds.  Find the angular velocity in rad/s.

26.5 rad/s.

A wheel rotates at 32.0 rad/s.  How many radians does it complete in 4.50 s?

144 radians.

A wheel of 1.00 m radius turns as 253 rpm.  Recall 1 revolution = 2π radius, and 1 minute = 60.0 seconds.  Find the linear speed of a point on the rim of the wheel.

26.5 m/s

The radius of the axle of a winch is 3.00 in. The length of the handle (radius of wheel) is 1.50 ft. What weight, in pounds, will be lifted by an effort of 73.0 lb.?

438

A system consisting of two fixed pulleys and two movable pulleys has a mechanical advantage of 4. If a force of 97.0 N is exerted, what weight, in N, is raised?

388

A resistance of 325 N is raised by using a ramp 5.76 m long and by applying a force of 75.0 N. How high, in meters, can it be raised?

1.33

A second-class lever has

a resistance arm shorter than the effort arm

The MA of a pair of pliers is 5.0/1. A force of 32 N is exerted on the handle. What force is exerted on a wire in the pliers?

160 N

A bicycle requires 1575 Nm of input but only puts out 1150 Nm of work, what is the bicycle’s efficiency?

73.0%

Efficiency is

a percentage

An inclined plane is 15.0 m long and 4.50 m high.  Find its mechanical advantage.

3.33

Find a gauge pressure of a tire, in lb/in^2, with an absolute pressure of 45.0 lb/in^2.

30.3

Find the density of a liquid, in lb/ft^3, that exerts a pressure of 0.400 lb/in^2 at a depth of 42.0 in.

16.5

A rock weighs 25.7 N in air and 21.8 N in water. What is the buoyant force of the water in newtons?

3.9

Bernoulli’s principle states that for the horizontal flow of a fluid through a tube, the sum of the pressure and energy of motion per unit volume is

Constant

The statement that the pressure applied to a confined liquid is transmitted without measurable loss throughout the entire liquid to all inner surfaces of the container is called

Pascal’s principle

The force applied to a unit area is called

Pressure

For an incompressible fluid, the flow rate is

Constant throughout the pipe

Find the absolute pressure in a bike tire with a gauge pressure of 205 kPa.  Recall that atmospheric pressure at standard temperature is 101 kPa or 14.7 lb/in².

306 kPa

Find the depth in a lake at which the pressure is 18500 lb/ft². Recall D_water=62.4 lb/ft³.

296 ft

A heating element operates on 115 V. If it has a resistance of 15.4 ohms, what current, in amps, does it draw?

7.47

Four resistors of 3.40 ohms, 6.54 ohms, 8.32 ohms, and 1.34 ohms are connected in series with a 12.0 V battery. Find the total resistance, in ohms, of the circuit.

19.60

Four resistors of 3.40 ohms, 6.54 ohms, 8.32 ohms, and 1.34 ohms are connected in parallel with a 12.0 V battery. Find the total resistance, in ohms, of the circuit.

.761

A cell has an emf of 1.50 V and an internal resistance of r = 0.0500 Ω. If there is 0.125 A in the cell, what voltage is applied to the external circuit?

1.49 V

The atomic particle that carries a positive charge is

the proton

The resistance of a wire is dependent on all of the following except

voltage