Conceptual Physics (TESC) Chapter 6

A 1-kg chunk of putty moving at 1 m/s collides with and sticks to a 5-kg bowling ball initially at rest. The bowling ball and putty then move with a momentum of

1 kg m/s

A rifle of mass 2 kg is suspended by strings. The rifle fires a bullet of mass 0.01 kg at a speed of 200 m/s. The recoil velocity of the rifle is about

1 m/s

A piece of putty moving with 1 unit of momentum strikes and sticks to a heavy bowling ball that is initially at rest. After the putty sticks to the ball, both move with a combined momentum of

1 unit

A bungee jumper attains a speed of 30 m/s just as the bungee cord begins to stretch. If the period of stretch is 2 s, the magnitude of the jumper's average deceleration is about

1.5 g

Two identical gliders slide toward each other on an air track. One moves at 1 m/s and the other at 2 m/s. They collide and stick. The combined mass moves at

1/2 m/s

A 1-kg glider and a 2-kg glider both slide toward each other at 1 m/s on an air track. They collide and stick. The combined mass moves at

1/3 m/s

A 1-kg chunk of putty moving at 1 m/s collides with and sticks to a 5-kg bowling ball that is initially at rest on a frictionless surface. The speed of the putty thereafter is

1/6 m/s

A 5-kg shark swimming at a speed of 1 m/s swallows an absent-minded 1-kg fish swimming toward it at 4 m/s. The speed of the shark after this meal is

1/6 m/s

Consider massive gliders that slide friction-free along a horizontal air track. Glider A has a mass of 1 kg, a speed of 1 m/s, and collides with Glider B that has a mass of 5 kg and is at rest. If they stick upon collision, their speed after collision will be

1/6 m/s

A ball is moving at 3 m/s and has a momentum of 48 kg m/s. What is the ball's mass

16 kg

A 5000-kg freight car moving at 2 m/s runs into a 10,000-kg freight car at rest. They couple upon collision and move away as one body at

2 m/s

A 1000-kg car moving at 10 m/s brakes to a stop in 5 s. The average braking force is

2000 N

A 4 kg ball has a momentum of 12 kg m/s. What is the ball's speed

3 m/s

A 5-kg fish swimming at a speed of 1 m/s swallows an absent-minded 1-kg fish at rest. The speed of the larger fish after this lunch is

5/6 m/s.

The change in momentum, in kg m/s, that occurs when a 1.0 kg ball travelling at 4.0 m/s strikes a wall and bounces back at 2.0 m/s is

6

A 5000-kg freight car runs into a 10,000-kg freight car at rest. They couple upon collision and move with a speed of 2 m/s. What was the initial speed of the 5000-kg car

6 m/s

If all people, animals, trains and trucks all over the world began to walk or run towards the east, then the

Earth would spin a bit slower

A car traveling along the highway needs a certain amount of force exerted on it to stop it in a certain distance. More stopping force is required when the car has

More mass; more momentum; and less stopping distance

The impulse-momentum relationship is a direct result of

Newton's 2nd law

The conservation of momentum is most closely related to

Newton's 3rd law

A sandbag is motionless in outer space. A second sandbag with 3 times the mass moving at 12 m/s collides with it. They stick together and move at a speed of

None of these

The force on an apple hitting the ground depends upon

The speed of the apple just before it hits; the time of impact with the ground; and whether or not the apple bounces.

Which of the following has the largest momentum relative to the Earth's surface

a pickup truck speeding along a highway

When you jump from an elevated position you usually bend your knees upon reaching the ground. By doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. In this way the average force your body experiences is

about 1/10 as great

Which would produce more force: driving into a very massive concrete wall with no "give," or having a head-on collision at the same speed with an identical car moving toward you with the same speed

both the same

You're driving down the highway and a bug spatters into your windshield. Which undergoes the greater change in momentum during the time of contact

both the same

A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is

doubled

According to the impulse-momentum equation Ft = change in (mv), a person will suffer less injury falling on a wooden floor which "gives" than on a more rigid cement floor. The "F" in the above equation stands for the force exerted on the

either the force on the person or the force on the floor

The force that accelerates a rocket in outer space is exerted on the rocket by the A) rocket's nose cone

exhaust gases.

A heavy truck and a small car rolling down a hill at the same speed are forced to stop in the same amount of time. Compared to the force that stops the car, the force needed to stop the truck is

greater

Momentum is transferred to the ground when an apple falls on it. The momentum absorbed by the ground is

greater than that of the apple only if the apple bounces

A karate expert executes a swift blow and breaks a cement block with her bare hand. The magnitude of the force experienced by her hand is

identical to the force applied to the block

A bullet is fired from a gun. The speed of the bullet will be about the same as the speed of the recoiling gun

if the mass of the bullet equals the mass of the gun

Compared to the force that brings a small car to a stop, the force required to bring a heavy truck to a stop

impossible to determine without additional information

Padded dashboards in cars are safer in an accident than no padded ones because an occupant hitting the dash has

increased time of impact

When you are in the way of a fast-moving object and can't get out of its way, you will suffer a smaller force of impact if you decrease its momentum over a

long time

Two objects have the same size and shape, but one is much heavier than the other. When they are dropped simultaneously from a tower, they reach the ground at the same time, but the heavier one has a greater

momentum

A large metal ball is shot from a cannon with a short barrel. If the same ball were to be shot from cannon with a longer barrel, its muzzle velocity would be

more

A golf ball moving forward with 1 unit of momentum strikes and bounces backward off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of

more than 1 unit

If a monkey floating in outer space throws his hat away, the hat and the monkey will both

move away from each other, but at different speeds

An astronaut , floating alone in outer space, throws a baseball. If the ball floats away at a speed of 20 meters per second, the astronaut will

move in the opposite direction, but at a lower speed

A large heavy truck and a small baby carriage roll down a hill. Neglecting friction, at the bottom of the hill, the baby carriage will have a greater

none of these

A 1-N apple falls to the ground. The apple hits the ground with an impact force of about

not enough information given to say

A rifle recoils while firing a bullet. The speed of the rifle's recoil is small because the

rifle has much more mass than the bullet

Compared to falling on a stone floor, a wine glass may not break when it falls on a carpeted floor because the

stopping time is longer on the carpet

It is correct to say that impulse is equal to

the change in momentum it produces

Suppose that a tiny gun made of a strong but very light material fires a bullet that is more massive than the gun itself. For such a weapon

the target would be safer than the shooter

A fan attached to an ice sailcraft stalled on a windless day blows air into the sail that bounces backward upon impact. The boat can

then move in the direction of the wind impact force

To catch a ball, a baseball player extends the hand forward before impact with the ball and then lets it ride backward in the direction of the ball's motion. Doing this reduces the force of impact on the player's hand principally because the

time of impact is increased.

Recoil is noticeable if we throw a heavy ball while standing on roller skates. If instead we go through the motions of throwing the ball but hold onto it, our net recoil will be

zero

Two billiard balls having the same mass and speed roll toward each other. What is their combined momentum after they meet

zero