Final Exam Review Chapters 11, 12, 14

Question A passenger in the rear seat of a car moving at a steady speed is at rest relative to: a)The side of the road b)A pedestrian on the corner ahead c)The front seat of the car d)The wheels of car

Answer C

Question What distance can be most accurately measured with a ruler? a)The length of a river b)The width of a book c)The distance between two cities d)The size of an object under a microscope

Answer B – the width of a book

Question A person drives north 3 blocks, then turns east and drives 3 blocks. The driver then turns south and drives 3 blocks. How could the driver have made the distance shorter while maintaining he same displacement? a)By driving east 3 blocks from the starting point b)By driving north 1 block and east 4 blocks c)By driving west 3 blocks from the starting point d)By driving back to the starting point by the same route

Answer A

Question Speed is the ratio of the distance an object moves to a)The amount of time needed to travel the distance b)The direction the object moves c)The displacement of the object d)The motion of the object

Answer A

Question A car traveled 88 km in 1 hour, 90 km in the next 2 hours, and then 76 km in 1 hour before reaching its destination. What was the car’s average speed? a)254 km/h b)63.5 km/h c)209 km/h d)74.5 km/h

Answer B

Question Vector addition is used when motion involves a)More than one distance b)More than one velocity c)More than one speed d)All of the above

Answer B

Question Which example identifies a change in motion that produces acceleration? a)A speed skater moving at a constant speed on a straight track b)A ball moving at a constant speed around a circular track c)A particle moving in a vacuum at constant velocity d)A vehicle moving down the street at a steady speed

Answer B

Question An object moving at 30 m/s takes 5 s to come to a stop. What is the object’s acceleration? a)30 m/s 2 b)-30 m/s 2 c)-6 m/s 2 d)6 m/s 2

Answer C

Question A person walks 1 mile every day for exercise, leaving her front porch at 9:00 A.M. and returning to her front porch at 9:25 A.M. What is the total displacement of her daily walk? a)1 mile b)0 c)25 minutes d)None of the above

Answer 0

Question A ball is rolled uphill a distance of 3 meters before it slows, stops, and begins to roll back. The ball rolls downhill 6 meters before coming to rest against a tree. What is the magnitude of the ball’s displacement? a)3 meters b)6 meters c)9 meters d)18 meters

Answer A

Question Instantaneous speed is measured a)At the starting point b)When the object reaches its destination c)At a particular instant d)Over the duration of the trip

Answer C

Question The slope of a line on a distance-time graph is a)Distance b)Time c)Speed d)Displacement

Answer C

Question The rate at which velocity changes is a)Speed b)Vectors c)Acceleration d)Motion

Answer C

Question Objects in free fall near the surface of the Earth experience a)Constant speed b)Constant velocity c)Constant acceleration d)Constant distance

Answer C

Question Suppose you increase your walking speed from 1 m/s to 3 m/s in a period of 2 s. What is your acceleration? a)1 m/s 2 b)2 m/s 2 c)4 m/s 2 d)6 m/s 2

Answer A

Question The slope of a speed-time graph indicates a)Direction b)Acceleration c)Velocity d)Speed

Answer B

Question An object that is accelerating may be a)Slowing down b)Gaining speed c)Changing direction d)All of the above

Answer D

Question Displacement and velocity are examples of ___________________________ because they have both direction and magnitude.

Answer Vectors

Question The SI unit for measuring __________________________ is the meter.

Answer Distance

Question A car’s speedometer measures _______________________________.

Answer Instantaneous Speed

Question Freely falling objects accelerate at 9.8 m/s 2 because the force of __________________________ acts on them.

Answer Gravity

Question Which is not a force? a)friction b)Gravity c)Momentum d)weight

Answer C - momentum

Question You push on a box and are unable to move it. What force opposes your push? a)Static friction b)Rolling friction c)Sliding friction d)Air resistance

Answer A – static friction

Question Air resistance depends on a)The velocity of a moving object b)The weight of a moving object c)The mass of a moving object d)The inertia of a moving object

Answer A – the velocity of a moving object

Question What force besides gravity acts on a projectile? a)Weak nuclear b)Electrical c)Magnetic d)Air resistance

Answer D – air resistance

Question Newton’s first law of motion is sometimes called the law of a)Inertia b)Conservation c)Momentum d)resistance

Answer A - inertia

Question A change of which of the following affects the weight of an object? a)Momentum b)Velocity c)Acceleration due to gravity d)friction

Answer C – acceleration due to gravity

Question Which represents Newton’s second law? a)V = d/t b)A = F/m c)F = mv d)F = 0

Answer B – a = F/m

Question For every action force there is a a)Reaction force b)Net force c)Friction force d)Unbalanced force

Answer A – reaction force

Question Momentum depends upon a)Force only b)Velocity and friction c)Weight and mass d)Mass and velocity

Answer D - Mass and velocity

Question What force holds the nucleus together?

Answer Strong nuclear

Question What happens to an object when an unbalanced force acts on it?

Answer It moves/accelerates

Question You push harder and harder on a box until it begins sliding across the floor. Which was the stronger of the forces acting on the box, static or sliding friction?

Answer static

Question What is the difference between mass and weight?

Answer Weight depends on gravity whereas mass doesn’t

Question What force is responsible for your socks sticking together after they have been in the clothes dryer?

Answer Electromagnetic force

Question What force is responsible for the orbits of the planets in the solar system?

Answer Gravity/centripetal force

Question When a tennis player practices by hitting a ball against a wall, which of Newton’s laws of motion is the player making use of?

Answer N3L

Question What are 2 ways in which the acceleration of an object can be increased? (1 point each)

Answer Decrease mass or increase force

Question Which statement about an object falling at terminal velocity is true? a)Unbalanced forces act on the object b)The net force acting on the object is zero c)The object is accelerating d)The object is traveling in a circular path e)No fluid friction acts on the object

Answer B

Question Which has the greatest momentum? a)A huge boulder at rest b)A small pebble that is tossed into the air c)A baseball after it is hit with a bat d)A small pebble at rest e)A car traveling on a highway

Answer e

Question Projectile motion is caused by a)The downward force of gravity b)An initial forward velocity c)The downward force of gravity and an initial forward velocity d)A final vertical velocity

Answer C

Question When opposite poles of two magnets are brought together, the poles ___________ each other.

Answer Attract

Question The SI unit of force is the

Answer Newton

Question A push or a pull is an example of a(n) ______________.

Answer force

Question A force acting on an object does no work if a. a machine is used to move the object. b. the force is not in the direction of the object’s motion. c. the force is greater than the force of friction. d. the object accelerates

Answer b

Question If you exert a force of 10.0 N to lift a box a distance of 0.75 m, how much work do you do? Don’t forget units!

Answer 7.5 J

Question If you exert a force of 500 N to walk 4 m up a flight of stairs in 4 s, how much power do you use?

Answer 500 W

Question Which of the following statements is true? a. To increase power, you can decrease the amount of work you do in a given amount of time, or you can do a given amount of work in less time. b. To increase power, you can decrease the amount of work you do in a given amount of time, or you can do a given amount of work in more time. c. To increase power, you can increase the amount of work you do in a given amount of time, or you can do a given amount of work in less time. d. To increase power, you can increase the amount of work you do in a given amount of time, or you can do a given amount of work in more time.

Answer c

Question A 750-W motor might also be rated as a a. 0.5-horsepower motor. b. 1-horsepower motor. c. 2-horsepower motor. d. 10-horsepower motor.

Answer B

Question When a machine does work, it can do all of the following EXCEPT a. change the direction of a force. b. increase a force and change the distance a force moves. c. increase the distance a force moves and change the direction of a force. d. increase a force and increase the distance a force moves.

Answer D

Question If you know the input distance and output distance of a machine, which of the following can you calculate? a.work b. actual mechanical advantage c. efficiency d. ideal mechanical advantage

Answer D

Question A 100-m long ski lift carries skiers from a station at the foot of a slope to a second station 40 m above. What is the IMA of the lift?

Answer 2.5

Question The efficiency of a machine is always less than 100 percent because a. a machine cannot have an IMA greater than 1. b. some work input is lost to friction. c. the work input is too small. d. the work output is too great.

Answer B

Question A motor with an efficiency rating of 80 percent must supply 300 J of useful work. What amount of work must be supplied to the motor?

Answer 375 J

Question What is the SI unit of work?

Answer joule

Question The actual mechanical advantage of a machine a. cannot be less than 1. b. decreases as the input distance increases. c. increases with greater friction. d. is less than the ideal mechanical advantage of the machine.

Answer D

Question If you have to apply 30 N of force on a crowbar to lift an rock that weights 330 N, what is the actual mechanical advantage of the crowbar?

Answer 11

Question A mechanical device requires 400 J of work to do 340 J of work in lifting a crate. What is the efficiency of the device?

Answer 85%

Question An inclined plane reduces the effort force by a. increasing the distance through which the force is applied. b. increasing the work. c. reducing the effort distance. d. reducing the work

Answer A

Question An ax is an example of a(n) _____________________.

Answer wedge

Question An example of a compound machine is a a.crowbar. b.bicycle. c. ramp. d. seesaw.

Answer B

Question The ________________ of a machine is the number of times that the machine increases the input force.

Answer Mechanical Advantage

Question A ___________________ can be described as an inclined plane wrapped around a wedge.

Answer screw

Question The ideal mechanical advantage of a third class lever is always ________________ 1. a.Greater than b.Less than c.Equal to

Answer B