48 terms

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

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

To catch a ball, a baseball player extends the hand forward before impacts 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 increased

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

1kgm/s

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 are the same

The impulse momentum relationship is a direct result of

Newtons 2nd Law

It is correct to say that impulse is equal to

the change in momentum it produces

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

rifle has much more mass than the bullet

The conservation of momentum is most closely related to

Newtons 3rd law

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

long time

Horses that move with the fastest linear speed on a merry-go-round are located

near the outside

A coin and a ring roll down an incline starting at the same time. The one to reach the bottom first will be the

coin

A torque acting on an object tends to produce

rotation

When a twirling ice skater brings her arms inward, her rotational speed

increases

For a system in mechanical equilibrium

the resultant forces and torques must both be zero

A car travels in a circle with constant speed. The net force on the car is

directed toward the center of the curve

On a balanced seesaw, a boy three times the mass as his partner sits

1/3 the distance from fulcrum

The rotational inertia of your leg is greater when your leg is

striaght

A piece of mud flies off the rim of a bycicle wheel. In what direction will it be going immediately after leaving the wheel? (Ignore gravity in this short time interval.)

On a line at a tangent to the edge of the wheel

The center of gravity of a circular disk of sheet metal is

at the center of the disk

In order to quadruple an objects kinectic energy, we must

double it

A 5kg ball collides head-on with a 10kg ball, which is stationary. The collision is inelastic. What statement is true?

The magnitude of the change in velocity the 5 kg ball experiences is greater than that if the 10kg ball.

It is correct to say that impulse is equal to

the change in momentum it produces.

The moon is moving clackwise in a circular orbit around the Earth. Imagine if gravity was shut off, throughout the solar system, at the instant the moon is in the poistion shown. How would the moon move, after gravity was shut off.

In the direction of the down arrow, in a straight line.

Which moves faster in m/s on a merry go round: a horse on the inside or a horse on the outside?

outside horse

When a rigid body rotates about a fixed axis all the points in the body have the same centripetal acceleration.

False

A smaller car and a large truck collide head-on. During the collision the small car experiences

a much larger acceleration than the truck

If you push an object a given distance,while applying twice the force, you do

twice as much work

What is the quantity used to measure an objects resistance to changes in rotational motion?

moment of inertia

A tall tree and short tree (both having the same wwidth and density) are cut at the base at the same time and begin tipping over. which tree hits the grounf first?

the small tree

When objects stick together after colliding, the collsion is completely elastic.

false

The type of energy that a swining pendulum has at the high point of its swing is

gravitational

The conservation of momentum is most closely realted to

Newtons 3rd law

The tyoe of energy that a swinging pendulum has at the low point of its swing is

kinetic

An object lifted 10 meters gains 200j of potential energy. If the same object is lifted 20 meters, its energy gain is

twice as much

Energy could be best described as

the capactiy to do work

Which of the following principles explains why guns recoil

Consservation of momentum

When doing somersaults, you'll more easily rotate when your body is

balled up

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

The rate of doing work, or transforming energy, can be measured in

watts

Three cars, x, y, 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 force exerted on each car is identical. After 10 secs which carhas the most amount of momentum?

they all have the same momentum

What form(s) of energy does the falling rubber ball have when it is halfway down?

Both kinetic and gravitational

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

A ball can be rolled down 3 different ramps. The final elevation loss of each ramp is the same. Neglecting friction, for which ramp will the speed of the ball be at the highest at the bottom?

The speed of the ball will be the same for all ramps.

A merry go round spins freely when Janice moes quickly to the center along a raduis of the merry go round. Its true to say that

the moment of the inertia of the system decreases and the angular speed increases

A 3kg blob of putty moving at 3m/s slams into a 4kg blob of putty at rest. Calculate the momentum of the 2 stuck together blobs of putty immedialty after colliding

9 kg m/s

How much work is required to lift a 2.5 kg object 6.0 meters?

150J

A moving object triples in mass, how much more momentu, does it have?

3x more momentum since the momentum directly depends on the mass.