Deck 6: Impulse and Linear Momentum

Question 1

A very light Ping-Pong ball moving east at a speed of 4 m/s collides with a very heavy stationary bowling ball.The Ping-Pong ball bounces back to the west,and the bowling ball moves very slowly to the east.On which object is the greater magnitude impulse exerted during the collision?

A)Neither; the same magnitude impulse was exerted on both.
B)On the Ping-Pong ball
C)On the bowling ball
D)It is impossible to tell since the actual mass values are not given.
E)It is impossible to tell since the velocities after the collision are unknown.

Answer 1

A

Question 2

A rocket explodes into two fragments,one 25 times heavier than the other.The magnitude of the momentum change of the lighter fragment is

A)25 times as great as the momentum change of the heavier fragment.
B)The same as the momentum change of the heavier fragment.
C)1/25 as great as the momentum change of the heavier fragment.
D)5 times as great as the momentum change of the heavier fragment.
E)1/4 as great as the momentum change of the heavier fragment.

Answer 2

B

Question 3

Three cars,car X,car Y,and car Z,begin accelerating from rest at the same time.Car X is more massive than car Y,which is more massive than car Z.The net accelerating force exerted on each car is identical.After 10 seconds,which car has the most amount of momentum?

A)They all have the same amount of momentum.
B)Car X
C)Car Y
D)Car Z

Answer 3

A

Question 4

A 2.0-kg ball moving eastward at 3.0 m/s suddenly collides with and sticks to a 4.0-kg ball moving northward at 2.0 m/s.What is the magnitude of the momentum of this system just after the collision?

A)14 kg ∙ m/s
B)2.0 kg ∙ m/s
C)10 kg ∙ m/s
D)6.0 kg ∙ m/s
E)8.0 kg ∙ m/s

Question 5

During World War I,Germany used a "Big Bertha" cannon to hurl shells into Paris 30 miles away.This gun also had a very long barrel.What was the reason for using a long barrel in these guns?

A)to exert a larger force on the shells
B)to reduce frictional losses
C)to allow the expanding gases from the gunpowder to exert a force on the bullets for a longer time
D)to increase the force exerted on the bullet by the expanding gases from the gunpowder
E)to reduce the force exerted on the bullet by the expanding gases from the gunpowder

Question 6

Consider two less-than-desirable options.In the first you are driving 30 mph and crash head-on into an identical car also going 30 mph.In the second option you are driving 30 mph and crash head-on into a stationary brick wall.In neither case does your car bounce back from the thing it hits,and the collision time is the same in both cases.Which of these two situations would result in the greater impact force exerted on your car?

A)hitting the other car
B)hitting the brick wall
C)The force would be the same in both cases.
D)None of the above choices are correct.

Question 7

A small car meshes with a large truck in a head-on collision.Which of the following statements concerning the magnitude of the momentum change during the collision is correct? (There could be more than one correct choice.)

A)The truck has the greater magnitude momentum change.
B)The small car has the greater magnitude momentum change.
C)The small car and the truck have the same magnitude momentum change.
D)The magnitude of the momentum change of each one is inversely proportional to its mass.
E)The magnitude of the momentum change of each one is directly proportional to its mass.

Question 8

A small car meshes with a large truck in a head-on collision.Which of the following statements concerning the magnitude of the average force during the collision is correct?

A)There is a greater average force exerted on the truck.
B)There is a greater average force exerted on the small car.
C)There is the same magnitude average force exerted on both the small car and the truck.
D)The force exerted on each object is inversely proportional to its mass.
E)The force exerted on each object is directly proportional to its mass.

Question 9

Two friends are standing on opposite ends of a canoe that is initially at rest with respect to a frictionless lake.The person in the front throws a very massive ball toward the back,and the person in the back catches it.After the ball is caught,the canoe is

A)moving backward.
B)stationary.
C)moving forward.

Question 10

You are standing on a skateboard,initially at rest.A friend throws a very heavy ball towards you.You have two choices about what to do with the ball: either catch the ball or deflect it back toward your friend with the same speed as it was originally thrown.Which choice should you make in order to maximize your speed on the skateboard?

A)Catch the ball.
B)Deflect the ball back.
C)Your final speed on the skateboard will be the same regardless whether you catch the ball or deflect the ball.

Question 11

Which of the following quantities are units of momentum? (There could be more than one correct choice.)

A)N ∙ m
B)kg ∙ s/m
C)kg ∙ m/s
D)N ∙ s
E)kg ∙ m²/s²

Question 12

A 0.14-kg baseball is dropped from rest from a height of 2.0 m above the ground.What is the magnitude of its momentum just before it hits the ground if we neglect air resistance?

A)0.28 kg ∙ m/s
B)0.88 kg ∙ m/s
C)0.44 kg ∙ m/s
D)0.62 kg ∙ m/s
E)1.4 kg ∙ m/s

Question 13

Identical forces are exerted for the same length of time on two different objects.The magnitude of the change in momentum of the lighter object is

A)smaller than the magnitude of the change in momentum of the larger mass object, but not zero.
B)larger than the magnitude of the change in momentum of the larger mass object.
C)exactly equal to the magnitude of the change in momentum of the larger mass object.
D)zero.
E)There is not enough information to answer the question.

Question 14

A small car meshes with a large truck in a head-on collision.Which of the following statements concerning the momentum during the collision are correct? (There could be more than one correct choice.)

A)The momentum of the truck is constant.
B)The momentum of the car is constant.
C)The car and the truck must undergo the same change in speed.
D)The momentum of the car and the momentum of the truck are each constant.
E)The momentum of the car-truck system is constant, but the momentum of each one separately is not constant.

Question 15

What is the magnitude of the momentum of a 0.140 kg baseball traveling at 45.0 m/s?

Question 16

A tiger is running in a straight line.If we double both the mass and speed of the tiger,the magnitude of its momentum will increase by what factor?

A)
B)2
C)4
D)8
E)16

Question 17

A very elastic rubber ball is dropped from a certain height and hits the floor with a downward speed v.Since it is so elastic,the ball bounces back with the same speed v going upward.Which of the following statements about the bounce are correct? (There could be more than one correct choice.)

A)The ball had the same momentum just before and just after the bounce.
B)The magnitude of the ball's momentum was the same just before and just after the bounce.
C)The ball's momentum was conserved during the bounce.
D)None of the above statements are correct.

Question 18

Which of the following quantities are units of impulse? (There could be more than one correct choice.)

A)N ∙ m
B)kg ∙ s/m
C)kg ∙ m/s
D)N ∙ s
E)kg ∙ m²/s²

Question 19

In a collision between two objects of unequal mass,which object receives a greater magnitude impulse?

A)the object of larger mass
B)the object of smaller mass
C)They receive equal magnitude impulses.

Question 20

A rubber ball and a lump of clay have equal mass.They are thrown with equal speed against a wall.The ball bounces back with nearly the same speed with which it hit.The clay sticks to the wall.Which one of these objects has the greater momentum change?

A)the ball
B)the clay
C)Both of them have the same non-zero momentum change.
D)Both of them have zero momentum change.

Question 21

A 0.330-kg volleyball is thrown vertically downward with a speed of 0.150 m/s in a place where g = 9.81 m/s².It takes it 0.0655 s to reach the ground.What is the magnitude of its momentum just before it hits the ground?

A)0.212 kg ∙ m/s
B)0.262 kg ∙ m/s
C)0.163 kg ∙ m/s
D)0.0216 kg ∙ m/s
E)0.0418 kg ∙ m/s

Question 22

Three objects are moving along a straight line as shown in the figure.Taking the positive direction to be to the right,what is the total momentum of this system?

A)+106 kg ∙ m/s
B)-106 kg ∙ m/s
C)+14.0 kg ∙ m/s
D)-14.0 kg ∙ m/s
E)0.00 kg ∙ m/s

Question 23

Two air track carts move along an air track towards each other.Cart A has a mass of 450 g and moves toward the right with a speed of 0.850 m/s.Cart B has a mass of 300 g and moves toward the left with a speed of 1.12 m/s.What is the total momentum of the two-cart system?

A)0.047 kg ∙ m/s toward the right
B)0.719 kg ∙ m/s toward the right
C)0.719 kg ∙ m/s toward the left
D)0.750 kg ∙ m/s toward the right
E)0.750 kg ∙ m/s toward the left

Question 24

In a police ballistics test,a 10.0-g bullet moving at 300 m/s is fired into a 1.00-kg block at rest.The bullet goes through the block almost instantaneously and emerges with 50.0% of its original speed.What is the speed of the block just after the bullet emerges?

A)1.50 m/s
B)2.97 m/s
C)3.00 m/s
D)273 m/s

Question 25

Two ice skaters suddenly push off against one another starting from a stationary position.The 45-kg skater acquires a speed of 0.375 m/s relative to the ice.What speed does the 60-kg skater acquire relative to the ice?

A)0.50 m/s
B)0.28 m/s
C)0.38 m/s
D)0.75 m/s
E)0.00 m/s

Question 26

A 100-g ball falls from a window that is 12 m above ground level and experiences no significant air resistance as it falls.What is its momentum when it strikes the ground?

A)3.3 kg ∙ m/s
B)4.8 kg ∙ m/s
C)1.8 kg ∙ m/s
D)1.5 kg ∙ m/s
E)2.4 kg ∙ m/s

Question 27

A dinner plate falls vertically to the floor and breaks up into three pieces,which slide horizontally along the floor.Immediately after the impact,a 200-g piece moves along the +x-axis with a speed of 2.00 m/s,a 235-g piece moves along the +y-axis with a speed of 1.50 m/s.The third piece has a mass of 100 g.What is the speed of the third piece?

A)2.51 m/s
B)2.57 m/s
C)3.50 m/s
D)5.33 m/s
E)6.83 m/s

Question 28

A 1200-kg cannon suddenly fires a cannonball at What is the recoil speed of the cannon? Assume that frictional forces are negligible and the cannon is fired horizontally.

A)2.9 m/s
B)35 m/s
C)3.5 m/s
D)3.2 m/s

Question 29

A 328-kg car moving at 19.1 m/s in the +x direction hits from behind a second car moving at in the same direction.If the second car has a mass of and a speed of right after the collision,what is the velocity of the first car after this sudden collision?

A)14.0 m/s
B)18.2 m/s
C)24.2 m/s
D)-14.0 m/s

Question 30

A 60-kg swimmer suddenly dives horizontally from a 150-kg raft with a speed of 1.5 m/s.The raft is initially at rest.What is the speed of the raft immediately after the diver jumps,assuming that the water has negligible effect on the raft during the jump?

Question 31

A dinner plate falls vertically to the floor and breaks up into three pieces,which slide horizontally along the floor.Immediately after the impact,a 320-g piece moves along the +x-axis with a speed of 2.00 m/s and a 355-g piece moves along the +y-axis with a speed of 1.50 m/s.The third piece has a mass of 100 g.In what direction relative to the +x-axis does the third piece move?

A)216.9° from the +x-axis
B)219.8° from the +x-axis
C)36.9° from the +x-axis
D)39.9° from the +x-axis
E)39.8° from the +x-axis

Question 32

Find the magnitude and direction of the net momentum of the system shown in the figure.Express the direction by giving the angle the net momentum makes with the +x-axis.

Question 33

A 0.140-kg baseball is dropped and reaches a speed of 1.20 m/s just before it hits the ground and bounces.It rebounds with an upward velocity of 1.00 m/s.What is the change of the ball's momentum during the bounce?

A)0.0280 kg ∙ m/s upwards
B)0.0280 kg ∙ m/s downwards
C)0.308 kg ∙ m/s upwards
D)0.308 kg ∙ m/s downwards
E)0.000 kg ∙ m/s

Question 34

A 600-kg car makes a 90° turn.Its speed before the turn is 21.0 m/s and after the turn it is 24.0 m/s.What is the magnitude of the change in the car's momentum during the turn?

A)19.1 × 1 kg∙m/s
B)10.2 × 1 kg∙m/s
C)9.55 × 1 kg∙m/s
D)12.0 × 1 kg∙m/s
E)22.2 × 1 kg∙m/s

Question 35

A 0.10-kg ball,traveling horizontally at 25 m/s,strikes a wall and rebounds at 19 m/s.What is the magnitude of the change in the momentum of the ball during the rebound?

A)1.2 kg ∙ m/s
B)1.8 kg ∙ m/s
C)4.4 kg ∙ m/s
D)5.4 kg ∙ m/s
E)72 kg ∙ m/s

Question 36

A 14,000-kg boxcar is coasting at 1.50 m/s along a horizontal track when it suddenly hits and couples with a stationary 10,000-kg boxcar.What is the speed of the cars just after the collision?

Question 37

A 1200-kg ore cart is rolling at 10.8 m/s across a flat friction-free surface.A crane suddenly drops of ore vertically into the cart.How fast does the cart move just after being loaded with the ore?

A)6.30 m/s
B)3.80 m/s
C)4.20 m/s
D)5.70 m/s

Question 38

A firecracker breaks up into two pieces,one of which has a mass of 200 g and flies off along the +x-axis with a speed of 82.0 m/s.The second piece has a mass of 300 g and flies off along the +y-axis with a speed of 45.0 m/s.What is the total momentum of the two pieces?

A)361 kg ∙ m/s at 56.3° from the +x-axis
B)93.5 kg ∙ m/s at 28.8° from the +x-axis
C)21.2 kg ∙ m/s at 39.5° from the +x-axis
D)361 kg ∙ m/s at 0.983° from the +x-axis
E)21.2 kg ∙ m/s at 56.3° from the +x-axis

Question 39

In a police ballistics test,2.00-g bullet traveling at 700 m/s suddenly hits and becomes embedded in a stationary 5.00-kg wood block.What is the speed of the block immediately after the bullet has stopped moving relative to the block?

Question 40

An empty train car of mass 2.0 x 10⁴ kg coasts along at 10 m/s.A 3000-kg boulder is suddenly dropped vertically into the car.Find the speed of the car immediately after the boulder is dropped in.

Question 41

A 475-gram ball is traveling horizontally at 12.0 m/s to the left when it is suddenly struck horizontally by a bat,causing it to reverse direction and initially travel at 8.50 m/s to the right.If the bat exerted an average force of 1275 N on the ball,for how long (in milliseconds)was it in contact with the ball?

Question 42

A batter exerts an average force of 8000 N to a baseball for 1.1 ms.What is the magnitude of the impulse exerted on the baseball by the bat?

Question 43

A steady horizontal force lasting for 2.1 s causes a 1.25 kg object to accelerate at 3.2 m/s² on a frictionless table.What impulse does this force exert on the object?

A)26 kg ∙ m/s
B)11 kg ∙ m/s
C)8.4 kg ∙ m/s
D)2.6 kg ∙ m/s

Question 44

The graph in the figure shows the x component F of the sum of the forces exerted for 10 s on a 100-kg crate.What is the change in the momentum of the crate during the 10 s that this force acts?

A)-100 kg ∙ m/s
B)-25 kg ∙ m/s
C)75 kg ∙ m/s
D)-75 kg ∙ m/s
E)25 kg ∙ m/s

Question 45

A batter hits a 0.140-kg baseball that was approaching him at 30 m/s and,as a result,the ball leaves the bat at 40 m/s in the reverse of its original direction.The ball remains in contact with the bat for 2.0 ms.What is the magnitude of the average force exerted by the bat on the ball?

Question 46

A golf ball of mass 0.050 kg is at rest on the tee.Just after being struck,it has a velocity of 102 m/s.If the club and ball were in contact for what is the average force exerted on the ball by the club?

A)6.3 kN
B)7.1 kN
C)5.5 kN
D)4.9 kN

Question 47

Two astronauts,of masses 60 kg and 80 kg,are initially right next to each other and at rest in outer space.They suddenly push each other apart.What is their separation after the heavier astronaut has moved 12 m?

A)9.0 m
B)16 m
C)21 m
D)24 m
E)28 m

Question 48

A 14-cm diameter champagne bottle rests on its side on top of a frictionless horizontal table.Suddenly,the cork pops and the bottle slides backward,covering a distance of in If the mass of the bottle is 500 times the mass of the cork,find the distance from the original position that the cork will land on the table.Neglect air resistance and assume that the cork is very small compared to the bottle.

A)3000 cm
B)60 m
C)85 m
D)8.5 cm

Question 49

A forklift pushes a 100-kg crate,starting from rest,exerting a horizontal force of magnitude F.The graph in the figure shows the x component of this force as a function of time.What is the instantaneous velocity of the crate at time t = 10 s?

A)25 cm/s
B)0.00 cm/s
C)75 cm/s
D)-25 cm/s
E)-75 cm/s

Question 50

Two astronauts,of masses 60 kg and 80 kg,are initially right next to each other and at rest in outer space.They suddenly push each other apart.How far has the heavier astronaut moved when the lighter astronaut has moved 12 m?

A)16 m
B)9.0 m
C)21 m
D)7.0 m
E)12 m

Question 51

A 0.140-kg baseball is thrown with a velocity of It is struck by the bat exerting an average force of 5000 N,which results in a velocity of 37.0 m/s in the opposite direction from the original velocity.How long were the bat and ball in contact?

A)1.79 × 10^-3 s
B)1.28 × 10^-2 s
C)3.07 × 10^-2 s
D)4.30 × 10^-3 s

Question 52

A 0.17-kg baseball is thrown with a speed of 38 m/s and it is hit straight back toward the pitcher with a speed of 62 m/s.What is the magnitude of the impulse exerted by the bat on the ball?

Question 53

A super dart of mass 20 g,traveling at 350 m/s,strikes a steel plate at an angle of 30° with the plane of the plate,as shown in the figure.It bounces off the plate at the same angle but at a speed of 320 m/s.What is the magnitude of the impulse that the plate exerts on the bullet?

A)0.52 N ∙ s
B)4.3 N ∙ s
C)300 N ∙ s
D)6.7 N ∙ s
E)0.30 N ∙ s

Question 54

Astronaut Jennifer's lifeline to her spaceship comes loose and she finds herself stranded,"floating" 100 m from the mothership.She suddenly throws her 2.00-kg wrench at 20 m/s in a direction away from the ship.If she and her spacesuit have a combined mass of 200 kg,how long does it take her to coast back to her spaceship?

A)1000 s
B)750 s
C)500 s
D)250 s
E)2.50 min

Question 55

A 0.140 kg baseball is thrown horizontally with a velocity of 28.9 m/s.It is struck with a constant horizontal force that lasts for 1.85 ms,which results in a velocity of 37.0 m/s in the opposite direction.What was the magnitude of the horizontal force?

A)0.613 kN
B)2.19 kN
C)2.80 kN
D)4.99 kN

Question 56

Jennifer hits a stationary 0.20-kg ball,and it leaves her racket at 40 m/s.Time-lapse photography shows that the ball was in contact with the racket for 40 ms.
(a)What average force did the ball exert on the racket?
(b)What is the ratio of this force to the gravitational force that Earth exerts on the ball?

Question 57

A girl of mass 55 kg throws a ball of mass 0.80 kg against a wall.The ball strikes the wall horizontally with a speed of and it bounces back with this same speed.The ball is in contact with the wall What is the magnitude of the average force exerted on the wall by the ball?

A)800 N
B)400 N
C)55,000 N
D)27,500 N
E)13,750 N

Question 58

A golf club exerts an average horizontal force of 1000 N on a 0.045-kg golf ball that is initially at rest on the tee.The club is in contact with the ball for 1.8 ms.What is the speed of the golf ball just as it leaves the tee?

A)30 m/s
B)35 m/s
C)40 m/s
D)45 m/s
E)50 m/s

Question 59

Calculate the impulse due to a force of that lasts for

A)6.3 kg∙ m/s
B)5.0 kg∙ m/s
C)5.7 kg∙ m/s
D)6.9 kg∙ m/s

Question 60

A 0.24 kg blob of clay is thrown at a wall with an initial horizontal velocity of If the clay comes to a stop in what is the average horizontal force exerted on the clay by the wall?

A)42 N
B)26 N
C)35 N
D)51 N

Question 61

A car (of mass 1500 kg)and a small truck (of mass 2000 kg)collide suddenly at right angles at an icy intersection.The car was originally traveling eastward at 20.0 m/s and the truck was traveling northward at 20.0 m/s just before the collision took place.What is the speed of the combined wreck just after the collision if the vehicles become enmeshed?

Question 62

A 900-kg car traveling east at 15.0 m/s suddenly collides with a 750-kg car traveling north at 20.0 m/s.The cars stick together after the collision.In what direction does the wreckage move just after the collision?

A)36.9° N of E
B)42.0° N of E
C)45.0° N of E
D)53.1° N of E
E)48.0° N of E

Question 63

A 900-kg car traveling east at 15.0 m/s suddenly collides with a 750-kg car traveling north at 20.0 m/s.The cars stick together after the collision.What is the speed of the wreckage just after the collision?

A)6.10 m/s
B)12.2 m/s
C)25.0 m/s
D)35.0 m/s
E)17.3 m/s

Question 64

An 80-kg man is skating northward and happens to suddenly collide with a 20-kg boy who is ice skating toward the east.Immediately after the collision,the man and boy are seen to be moving together at 2.5 m/s in a direction 60° north of east.How fast was the boy moving just before the collision?

Question 65

A puck with a mass m₁ = 50 g moving at 1.0 m/s approaches a stationary puck with a mass m₂ = 100 g on a frictionless air table,and they undergo a sudden two-dimensional elastic collision.After the collision,both pucks have identical speeds,but travel in different directions.What is the angle between the original and final paths of puck with mass m₁?

A)30°
B)60°
C)90°
D)120°
E)150°

Question 66

A batter hits a foul ball.The 0.14-kg baseball that was approaching him at 40 m/s leaves the bat at 30 m/s in a direction perpendicular to the line between the batter and the pitcher.What is the magnitude of the impulse exerted on the baseball?

A)9.8 N ∙ s
B)1.4 N ∙ s
C)3.5 N ∙ s
D)5.6 N ∙ s
E)7.0 N ∙ s

Question 67

A 1500-kg car traveling at 90 km/h toward the east suddenly collides with a 3000-kg car traveling at 60 km/h toward the south.The two cars stick together after the collision.What is the speed of the cars after collision?

A)8.3 m/s
B)14 m/s
C)17 m/s
D)22 m/s

Question 68

A fire hose is turned on the door of a burning building in order to knock the door down.This requires a force of 1000 N.If the hose delivers 40 kg of water per second,what is the minimum velocity of the stream needed to knock down the door,assuming the water doesn't bounce back?

A)15 m/s
B)20 m/s
C)25 m/s
D)30 m/s

Question 69

A 1000-kg whale swims horizontally to the right at a speed of 6.0 m/s.It suddenly collides directly with a stationary seal of mass 200 kg.The seal grabs onto the whale and holds fast.What is the speed of these two sea creatures just after their collision? You can neglect any drag effects of the water during the collision.

A)0.00 m/s
B)3.0 m/s
C)4.0 m/s
D)5.0 m/s
E)6.0 m/s

Question 70

A 900-kg car traveling 30.0° south of east at 12.0 m/s suddenly collides with a 750-kg car traveling north at 17.0 m/s.The cars stick together after colliding.What is the speed of the wreckage just after the collision?

A)7.21 m/s
B)12.2 m/s
C)20.4 m/s
D)25.0 m/s
E)17.3 m/s

Question 71

A 2200-kg auto moving northward at 12.0 m/s runs into a 3800-kg truck which is also moving northward,but at 5.00 m/s.If the vehicles lock bumpers,how fast are they moving just after the collision?

Question 72

A force of 5.3 N is needed to hold on to an umbrella in a strong wind.If the air molecules each have a mass of 4.7 ×10^-26 kg,and each one strikes the umbrella (without rebounding)with a speed of 2.0 m/s in the same direction,how many molecules strike the umbrella each second? Assume that the wind blows horizontally so that the gravitational force exerted on the air molecules can be neglected.

Question 73

A 0.140-kg baseball is dropped from rest.It has a speed of 1.20 m/s just before it hits the ground,and it rebounds with an upward speed of 1.00 m/s.The ball is in contact with the ground for 0.0140 s.What is the average force exerted by the ground on the ball during the time of contact?

A)2.00 N upwards
B)2.00 N downwards
C)22.0 N upwards
D)22.0 N downwards
E)0.00 N

Question 74

Two vehicles approach a right angle intersection and then suddenly collide.After the collision,they become entangled.If their mass ratios were 1:4 and their respective speeds as they approached the intersection were both 13 m/s,find the magnitude and direction of the final velocity of the wreck.

A)11 m/s at 14° with respect to the original direction of the lighter car
B)16 m/s at 76° with respect to the original direction of the lighter car
C)11 m/s at 76° with respect to the original direction of the lighter car
D)26 m/s at 76° with respect to the original direction of the lighter car
E)16 m/s at 14° with respect to the original direction of the lighter car

Question 75

A 1000-kg whale swims horizontally to the right at a speed of 6.0 m/s.It suddenly collides directly with a stationary seal of mass 200 kg.The seal grabs onto the whale and holds fast.What is the momentum of these two sea creatures just after their collision? You can neglect any drag effects of the water during the collision.

A)0.00 kg ∙ m/s
B)1200 kg ∙ m/s
C)2000 kg ∙ m/s
D)7200 kg ∙ m/s
E)6000 kg ∙ m/s

Question 76

A 1200-kg car moving at suddenly collides with a stationary car of mass If the two vehicles lock together,what is their combined velocity immediately after the collision?

A)6.9 m/s
B)8.6 m/s
C)12.1 m/s
D)5.5 m/s

Question 77

A car heading north suddenly collides at an intersection with a truck of the same mass heading east.If they lock together and travel at at 15° north of east just after the collision,how fast was the car initially traveling?

A)14 m/s
B)7 m/s
C)28 m/s
D)11 m/s

Question 78

A very small 51-g steel ball is released from rest and falls vertically onto a steel plate.The ball strikes the plate and is in contact with it for 0.50 ms.The ball rebounds elastically (at the same speed)and returns to its original height.The total time interval for a round trip is 3.00 s.What is the magnitude of the average force exerted on the ball by the plate during contact with the plate?

A)3000 N
B)1500 N
C)2490 N
D)2000 N
E)3500 N

Question 79

A block of mass m = 5.6 kg,moving on a frictionless surface with a velocity of to the right,collides with a block of mass M at rest,as shown in the figure.After the collision,the 5.6-kg block recoils with a velocity of to the left.If the blocks are in contact for 0.20 s,what is the magnitude of the average force exerted on the 5.6-kg block,while the two blocks are in contact?

A)202 N
B)192 N
C)182 N
D)0 N
E)0 N

Question 80

A block of mass m = 34 kg and speed V is behind a block of mass M = 81 kg and speed of as shown in the figure.The surface is frictionless and the blocks collide and couple.After the collision,the blocks have a common speed of What is the magnitude of the impulse on the 34-kg block due to the collision?

A)32 N ∙ s
B)14 N ∙ s
C)41 N ∙ s
D)57 N ∙ s
E)73 N ∙ s