END OF YEAR PART 2

MOMENTUM & COLLISIONS

100

A truck driving along a highway road has a large quantity of momentum. If it moves at the same speed but has twice as much mass, its momentum is ________________. a. zero b. quadrupled c. doubled d. unchanged

C

200

A 4 kg object has a momentum of 12 kg•m/s. The object's speed is ___ m/s. a. 3 b. 4 c. 12 d. 48 e. none of these.

A

300

Which of the following objects have momentum? Include all that apply. a. An electron is orbiting the nucleus of an atom. b. A UPS truck is stopped in front of the school building. c. A Yugo (a compact car) is moving with a constant speed. d. A small flea walking with constant speed across Fido's back. e. The high school building rests in the middle of town.

A, C, and D

400

Which of the following statements are true about impulse? A)Impulse is a force. B)Impulse is a vector quantity. C)An object which is traveling east would experience a westward directed impulse in a collision. D)Objects involved in collisions encounter impulses. E)The Newton is the unit for impulse. F)The kg•m/s is equivalent to the units on impulse. G)An object which experiences a net impulse will definitely experience a momentum change. H)In a collision, the net impulse experienced by an object is equal to its momentum change. I)A force of 100 N acting for 0.1 seconds would provide an equivalent impulse as a force of 5 N acting for 2.0 seconds.

BDFGHI

500

Which of the following statements are true about momentum? A)Momentum is a vector quantity. B)The standard unit on momentum is the Joule. C)An object with mass will have momentum. D)An object which is moving at a constant speed has momentum. E)An object can be traveling eastward and slowing down; its momentum is westward. F)Momentum is a conserved quantity; the momentum of an object is never changed. G)The momentum of an object varies directly with the speed of the object. H)Two objects of different mass are moving at the same speed; the more massive object will have the greatest momentum. I)A less massive object can never have more momentum than a more massive object. J)Two identical objects are moving in opposite directions at the same speed. The forward moving object will have the greatest momentum. K)An object with a changing speed will have a changing momentum.

ADGHK

WORK, ENERGY & POWER

100

What are the units of work and energy?

Joule

200

Which of the following statements are true about potential energy? Include all that apply. A)Moving objects cannot have potential energy. B)Potential energy is the energy stored in an object due to its position. C)Both gravitational and elastic potential energy are dependent upon the mass of an object. D)The gravitational potential energy of an object is dependent upon the mass of the object. E)If the mass of an elevated object is doubled, then its gravitational potential energy will be doubled as well. F)Gravitational potential energy is lost as objects free-fall to the ground.

BDEF

300

Which of the following statements are true about kinetic energy? Include all that apply. A)Kinetic energy is the form of mechanical energy which depends upon the position of an object. B)If an object is at rest, then it does not have any kinetic energy. C)If an object is on the ground, then it does not have any kinetic energy. D)The kinetic energy of an object is dependent upon the weight and the speed of an object. E)Faster moving objects always have a greater kinetic energy. F)More massive objects always have a greater kinetic energy. G)Kinetic energy is a scalar quantity.

BG

400

Which of the following statements are true about power? Include all that apply. A)Power is a time-based quantity. B)Power refers to how fast work is done upon an object. C)Powerful people or powerful machines are simply people or machines which always do a lot of work. D)A force is exerted on an object to move it at a constant speed. The power delivered by this force is the magnitude of the force multiplied by the speed of the object. E)The standard metric unit of power is the Watt. F)If person A and person B do the same job but person B does it faster, then person A does more work but person B has more power. G)The Newton•meter is a unit of power.

ABDE

500

Which of the following statements are true about work? Include all that apply. A)Work is a form of energy. B)A Watt is the standard metric unit of work. C)Units of work would be equivalent to a Newton times a meter. D)A kg•m2/s2 would be a unit of work. E)Work is a time-based quantity; it is dependent upon how fast a force displaces an object. F)Superman applies a force on a truck to prevent it from moving down a hill. This is an example of work being done. G)An upward force is applied to a bucket as it is carried 20 m across the yard. This is an example of work being done. H)A force is applied by a chain to a roller coaster car to carry it up the hill of the first drop of the Shockwave ride. This is an example of work being done. I)The force of friction acts upon a softball player as she makes a headfirst dive into third base. This is an example of work being done.

ACDHI

WORK, ENERGY & POWER

100

A 1000-kg car is moving at 40.0 km/hr when the driver slams on the brakes and skids to a stop (with locked brakes) over a distance of 20.0 meters. How far will the car skid with locked brakes if it is traveling at 120. km/hr? a. 20.0 m b. 60.0 m c. 90.0 m d. 120. m e. 180. m

E

200

A platform diver weighs 500 N. She steps off a diving board that is elevated to a height of 10 meters above the water. The diver will possess ___ Joules of kinetic energy when she hits the water. a. 10 b. 500 c. 510 d. 5000 e. more than 5000 .

D

300

A 10-Newton object moves to the left at 1 m/s. Its kinetic energy is approximately ____ Joules. a. 0.5 b. 1 c. 10 d. more than 10

A

400

Which requires more work: lifting a 50.0 kg crate a vertical distance of 2.0 meters or lifting a 25.0 kg crate a vertical distance of 4.0 meters? a. lifting the 50 kg crate b. lifting the 25 kg crate c. both require the same amount of work

C

500

Using 1000. J of work, a small object is lifted from the ground floor to the third floor of a tall building in 20.0 seconds. What power was required in this task? a. 20 W b. 50 W c. 100 W d. 1000 W e. 20000 W

B

WORK, ENERGY & POWER

100

Approximate the work required lift a 2.5-kg object to a height of 6.0 meters.

~150 J

200

Eddy, whose mass is 65.0-kg, climbs up the 1.60-meter high stairs in 1.20 s. Approximate Eddy's power rating.

P = 849 Watts

300

Missy Diwater, the former platform diver for the Ringling Brother's Circus, had a kinetic energy of 12 000 J just prior to hitting the bucket of water. If Missy's mass is 40 kg, then what is her speed?

v = 24.5 m/s

400

A 221-gram ball is thrown at an angle of 17.9 degrees and a speed of 36.7 m/s from the top of a 39.8-m high cliff. Determine the impact speed of the ball when it strikes the ground. Assume negligible air resistance.

46.1 m/s

500

A 51.7-kg hiker ascends a 43.2-meter high hill at a constant speed of 1.20 m/s. If it takes 384 s to climb the hill, then determine A) kinetic energy change of the hiker. B) the potential energy change of the hiker. C) the work done upon the hiker. D) the power delivered by the hiker.

Delta KE = 0 J Delta PE = +21900 J W = +21900 J P = 57.0 Watts

UNIVERSAL LAW OF GRAVITATION

100

Determine the force of gravitational attraction between the earth (m = 5.98 x 1024 kg) and a 70-kg physics student if the student is standing at sea level, a distance of 6.38 x 106 m from earth's center.

686 N

200

Determine the force of gravitational attraction between the earth (m = 5.98 x 1024 kg) and a 70-kg physics student if the student is in an airplane at 40000 feet above earth's surface. This would place the student a distance of 6.39 x 106 m from earth's center.

684 N

300

Suppose that two objects attract each other with a gravitational force of 16 units. If the distance between the two objects is doubled, what is the new force of attraction between the two objects?

F = 4 units

400

Suppose that two objects attract each other with a gravitational force of 16 units. If the distance between the two objects is reduced in half, then what is the new force of attraction between the two objects?

F = 64 units

500

Suppose that two objects attract each other with a gravitational force of 16 units. If the mass of both objects was doubled, and if the distance between the objects remained the same, then what would be the new force of attraction between the two objects?

F = 64 units