Transcript Momentum - lcusd.net

Momentum
Which object has the greatest momentum?
(A) a 5.00-kg mass moving at 10.0 m/s
(B) a 10.0-kg mass moving at 1.00 m/s
(C) a 15.0-kg mass moving at 10.0 m/s
(D) a 20.0-kg mass moving at 1.00 m/s
What is the speed of a 1.0×103-kg car that has
a momentum of 2.0×104 kg•m/ s east?
(A) 5.0 × 10–2 m/s
(B) 2.0 × 101 m/s
(C) 1.0 × 104 m/s
(D) 2.0 × 107 m/s
Impulse
Which two quantities can be expressed using
the same units?
(A) energy and force
(B) impulse and force
(C) momentum and energy
(D) impulse and momentum
A 60-kg rollerskater exerts a 10-N force on a
30-kg rollerskater for 0.20 second. What is
the magnitude of the impulse applied to the
30-kg rollerskater?
(A) 50 N•s
(B) 2.0 N•s
(C) 6.0 N•s
(D) 12 N•s
A 60-kg rollerskater exerts a 10-N force on a
30-kg rollerskater for 0.20 second. What is
the magnitude of the change in momentum
applied to the 30-kg rollerskater?
(A) 50 kg•m/s
(B) 2.0 kg•m/s
(C) 6.0 kg•m/s
(D) 12 kg•m/s
A 60-kg rollerskater exerts a 10-N force on a
30-kg rollerskater for 0.20 second. What is
the magnitude of the change in momentum
applied to the 60-kg rollerskater?
(A) 50 kg•m/s
(B) 2.0 kg•m/s
(C) 6.0 kg•m/s
(D) 12 kg•m/s
A 0.149-kilogram baseball, initially moving at
15 meters per second, is brought to rest in
0.040 second by a baseball glove on a
catcher’s hand. What is the magnitude change
in momentum exerted on the ball by the glove?
A 0.149-kilogram baseball, initially moving at
15 meters per second, is brought to rest in
0.040 second by a baseball glove on a
catcher’s hand. The magnitude of the average
force exerted on the ball by the glove is
(A) 2.2 N
(B) 2.9 N
(C) 17 N
(D) 56 N
Which situation will produce the greatest
change of momentum for a 1.0-kilogram cart?
(A) accelerating it from rest to 3.0 m/s
(B) accelerating it from 2.0 m/s to 4.0 m/s
(C) applying a net force of 5.0 N for 2.0 s
(D) applying a net force of 10.0 N for 0.5 s
A 0.15-kilogram baseball moving at 20 m/s
is stopped by a catcher in 0.010 second. The
average force stopping the ball is
(A) 3.0×10–2 N
0
(B) 3.0×10 N
1
(C) 3.0×10 N
2
(D) 3.0×10 N
A 6.0-kilogram block, sliding to the east
across a horizontal, frictionless surface with a
momentum of 30 kg•m /s, strikes an obstacle.
The obstacle exerts an impulse of 10 N•s to
the west on the block. The speed of the block
after the collision is
(A) 1.7 m/s
(C) 5.0 m/s
(B) 3.3 m/s
(D) 20. m/s
Elastic
Ball A of mass 5.0 kg moving at 20 m/s
collides with ball B of unknown mass moving
at 10 m/s in the same direction. After the
collision, ball A moves at 10 m/s and ball B
at 15 m/s, both still in the same direction.
What is the mass of ball B?
(A) 6.0 kg
(B) 2.0 kg
(C) 10. kg
(D) 12 kg
A 1.2-kg block and a 1.8-kg block are initially
at rest on a frictionless, horizontal surface.
When a compressed spring between the blocks
is released, the 1.8-kg block moves to the right
at 2.0 m/s. What is the speed of the 1.2-kg
block after the spring is released?
(A) 1.4 m/s
(B) 2.0 m/s
(C) 3.0 m/s
(D) 3.6 m/s
Inelastic
A 3.0-kg steel block is at rest on a friction-less
horizontal surface. A 1.0-kg lump of clay is
propelled horizontally at 6.0 m/s toward the
block. Upon collision, the clay and steel block
stick together and move to the right with a
speed of
(A) 1.5 m/s
(B) 3.0 m/s
(C) 6.0 m/s
(D) 2.0 m/s
A woman (60-kg) with horizontal velocity (6
m/s) jumps off a dock into a stationary boat
(120 kg). After landing in the boat, the
woman and the boat move with velocity v2.
Find v2
A 3.1-kilogram gun initially at rest is free to
move. When a 0.015-kilogram bullet leaves
the gun with a speed of 500 m/s, what is the
speed of the gun?
(A) 0.0 m/s
(B) 2.4 m/s
(C) 7.5 m/s
(D) 500 m/s
At the circus, a 100-kg clown is fired at 15
m/s from a 500-kg cannon. What is the recoil
speed of the cannon?
(A) 75 m/s
(B) 3.0 m/s
(C) 15 m/s
(D) 5.0 m/s
An 8.00-kilogram ball is fired horizontally
from a 1.00 × 103-kg cannon initially at rest.
After having been fired, the momentum of
the ball is 2.40 × 103 kg•m/s east.
Calculate the magnitude of the cannon’s
velocity after the ball is fired.
An 8.00-kilogram ball is fired horizontally
from a 1.00 × 103-kg cannon initially at rest.
After having been fired, the momentum of
the ball is 2.40 × 103 kg•m/s east.
Calculate the magnitude of the cannon ball’s
velocity after itis fired.
A 50-kilogram child running at 6.0 meters per
second jumps onto a stationary 10-kilogram
sled. The sled is on a level frictionless surface.
Calculate the speed of the sled with the child
after she jumps onto the sled.
A 1200-kilogram car moving at 12 meters per
second collides with a 2300-kilogram car that
is waiting at rest at a traffic light. After the
collision, the cars lock together and slide.
Eventually, the combined cars are brought to
rest by a force of kinetic friction as the rubber
tires slide across the dry, level, asphalt road
surface.
Calculate the speed of the locked-together
cars immediately after the collision.
Extra
A 2.0-kg laboratory cart is sliding across a
horizontal frictionless surface at a constant
velocity of 4.0 m/s east. What will be the
cart’s velocity after a 6.0-Newton westward
force acts on it for 2.0 seconds?
(A) 2.0 m/s east
(B) 10 m/s east
(C) 2.0 m/s west
(D) 10 m/s west
A 1,200-kg car traveling at 10 m/s hits a tree
and is brought to rest in 0.10 second. What is
the magnitude of the average force acting on
the car to bring it to rest?
(A) 1.2×102 N
(B) 1.2×103 N
4
(C) 1.2×10 N
5
(D) 1.2×10 N
A 50-kg student threw a 0.40-kg ball with a
speed of 20 m/s. What was the magnitude of
the impulse that the student exerted on the
ball?
(A) 8.0 N•s
(B) 78 N•s
2
(C) 4.0 × 10 N•s
(D) 1.0 × 103 N•s
The instant before a batter hits a 0.14kilogram baseball, the velocity of the ball is
45 meters per second west. The instant after
the batter hits the ball, the ball’s velocity is 35
meters per second east. The bat and ball are in
contact for 1.0 × 10–2 second. Calculate the
initial momentum of the ball.
The instant before a batter hits a 0.14kilogram baseball, the velocity of the ball is
45 meters per second west. The instant after
the batter hits the ball, the ball’s velocity is 35
meters per second east. The bat and ball are in
contact for 1.0 × 10–2 second. Calculate the
final momentum of the ball.
The instant before a batter hits a 0.14kilogram baseball, the velocity of the ball is
45 meters per second west. The instant after
the batter hits the ball, the ball’s velocity is 35
meters per second east. The bat and ball are in
contact for 1.0 × 10–2 second. Calculate the
change in momentum of the ball.
The instant before a batter hits a 0.14kilogram baseball, the velocity of the ball is
45 meters per second west. The instant after
the batter hits the ball, the ball’s velocity is 35
meters per second east. The bat and ball are in
contact for 1.0 × 10–2 second. Calculate the
impulse that acted on the ball.
The instant before a batter hits a 0.14-kg
baseball, the velocity of the ball is 45 meters
per second west. The instant after the batter
hits the ball, the ball’s velocity is 35 meters
per second east. The bat and ball are in
contact for 1.0 × 10–2 second. Calculate the
magnitude of the average force the bat exerts
on the ball while they are in contact.
Calculate the magnitude of the impulse
applied to a 0.75-kilogram cart to change its
velocity from 0.50 meter per second east to
2.00 meters per second east.
A 1000-kilogram car traveling due
east at 15 meters per second is hit
from behind and receives a forward
impulse of 6000 Newton-seconds.
Determine the magnitude of the car’s
change in momentum due to this
impulse.
A 60-kilogram student jumps down from a
laboratory counter. At the instant he lands on
the floor his speed is 3 meters per second. If
the student stops in 0.2 second, what is the
average force of the floor on the student?
(A) 1×10–2 N
(B) 9×102 N
2
(C) 1×10 N
(D) 4N
A motorcycle being driven on a dirt path hits a rock.
Its 60-kilogram cyclist is projected over the
handlebars at 20 meters per second into a haystack.
If the cyclist is brought to rest in 0.50 second, the
magnitude of the average force exerted on the
cyclist by the haystack is
(A) 6.0 × 101 N
(B) 5.9 × 102 N
(C) 1.2 × 103 N
(D) 2.4 × 103 N
A 2.0-kg body is initially traveling at a
velocity of 40 m/s east. If a constant force of
10 Newtons due east is applied to the body
for 5.0 seconds, the final speed of the body is
(A) 15 m/s
(B) 65 m/s
(C) 25 m/s
(D) 130 m/s