Physics test chapter 6

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

1 kg 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 . Both move with a combined momentury 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 2 s while coming to a halt , the jumper's average deceleration is about

1.5g

Two identical gliders slide towards each other on an air track. One moves at 1 m/s and the other at 2 m/s. They collied, stick together, and 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 5 - kg shark swimming at I ms swallows an absent - minded 1 - kg fish swimming toward it at 4 m / s The speed of the shark after his meal is

1/6 m/s

A large heavy tro and a small baby carriage rol down a hill Neglecting friction , at the bottom of the hill , the baby carriage will likely have

Less momentum

A same - size iron ball and wooden ball are dropped simultaneously from a tower and reach the ground at the same time . The iron ball has a greater

Momentum

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 diffrent speeds

An astronaut floating alone in outer space throws a baseball . If the ball moves away at 20 m / s , the astronaut will

Move in an opposite direction at a lower speed

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

Moves in the direction of the wind impact force .

The impulse - momentum relationship is a direct result of

Newtons 2nd law

The conservation of momentum is most closely related to

Newtons 3rd law

Two identical freight cars roll on a level track . They collide , couple together , and roll away in the direction of

The faster car

A tiny gun made of a strong but very light material fires a bullet more masive than the gun itself . For such a weapon

The target would be safer than the shooter

The total momentum of a flock of identical birds could be zero only if the birds are

flying in different directions.

When Peter tosses an egg against a sagging sheet the egg doesn't break due to

neither of these

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

stopping time is longer on the carpet

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

5/6 m / s .

Two 500 kg rail cars roll without friction (one at 1 m/s the other at 2 m/s) toward each other on a level track. They collied, couple, and roll together with a combined momentum of

5000 kg m/s

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

6 kg m/s

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

6 m / s

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

A pickup truck speeding along a highway

When a vertically falling firecracker bursts , the vector sum of momentum fragments

both of these

The mass of a ball moving at 3 m / s with a momentum of 48 kg m / s is

16 kg

A 5000 - kg freight car moving at 2 m / s collides with a 10,000 - kg freight car at rest . They couple upon collision and move away at

2 m/s

The average braking force of a 1000 - kg car moving at 10 m / s braking to a stop in 5 sis

2000 n

The speed of a 4 - kg ball with a momentum of 12 kg m / s is

3 m/s

A motorcycle of mass 100 kilograms slowly rolls off the edge of a cliff and falls for three seconds before reaching the bottom of a gully. Its momentum upon hitting the ground is

3,000 kg m/s

Two vehicles with equal magnitudes of momentum traveling at right angles to each other undergo an inelastic collision The combined wreck noves in a direction

Aat 45 degrees to the direction of either car before collision

When you jump from an elevated postition you usually bend your knees upon reaching the ground which makes the time of the contact about 10 times that of a stiff legged landing. In this way the average force your body experience is

About 1/10 as great

The force on a dropped apple hitting the ground depends upon

All of the above

required if the car hast A car traveling along the highway brakes to a stop over a certain distance . More braking force is

All of the above

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

The greater efficiency achieved with the curved blades of a Pelton wheel is due to .

Bouncing

A cannonball following a parabolic path explodes into fragments . The momentum of the fragments

Continue along a path as if the explosion didnt occur

If all people , animals , trains and trucks all over the world began to walk or run towards the east opposite the direction of Earth's spin ) , then

Earth would spin a bit slower

Which has the greater momentum when moving

Either of these depending on speed

A firecracker bursts while freely falling . The combined momentum of its fragments

Equals the momentum of the firecracker at the time of burst

The force that acceleates a rocket in outer space is exerted on the rocket by the

Exhaust gas

) 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 with the force that stops the car , the force needed to stop the truck is

Greater

Two vehicles with equal magnitudes of momentum traveling at right angles to each other undergo an inelastic collision The magnitude of momentum for the combined wreck is

Greater than the magnitude of momentum of either car before collision

Whether a truck comes to a stop by crashing into a haystack or a brick wall , the stopping force is

Greater with the brick wall

hitting the dashboard encounter Padded dashboards in cars are safer in an accident than non padded ones because passengers

Lengthened time of contact

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

Zero

Whether a truck comes to a stop by crashing into a haystack or brick wall, the impulse is

both the same

Which produces more fora drving into a very massive concrete wall with no give or having a head - on collision with an identical car moving toward you at the same speed

both the same

A cannon recoils while firing a cannonball . The speed of the cannon's recoil is relatively small because the

cannon has much more mass than the cannonball

When bullets are fired from an airplane in the forward direction the momentum of the airplane is

decreased

An open freight car rolls friction free along a horizontal track in a pouring rain that falls vertically As water accumulates in the car , the car's speed

decreases

When Freddy Frog drops vertically from a tree onto a horizontally - moving skateboard , the speed of the skateboard

decreases

A softer landing occurs when an falling object bounces from a surface

in a extended time

When a boxer moves into an oncoming punch the force experienced is

increased

To catch a fast moving ball you extend of the ball's motion Doing this reduces the force of contact on your your hand forward before contact with the ball and let it ride backward in the direction hand principally because the

time of contact is increased

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

twice