motion
A stone with an initial velocity of zero is dropped from a bridge above a river. After 3 s, the stone strikes the water below the bridge. Approximately how fast is the stone traveling when it strikes the water?
30m/s
Which of the following measurements is NOT a Scalar?
:
Time
Speed
Distance
Displacement
displacement
A child riding a merry-go-round feels a centripetal force. How would the magnitude of the acceleration change if the velocity doubled (2x)?
decrease to one quarter (¼ x)
double (2x)
quadrupled (4x)
decrease to one half (½ x)
quadrupled 4x
A layer of padding is added to car dashboards because it can reduce some injuries during a collision. How does the padded dashboard make people safer?
increase the time of the impact during collision
How high does a 0.4 kg piece of cheese need to be raised above the ground for the cheese-Earth system to have a gravitational potential energy of 25 J?
h=6.37
TRUE or FALSE?
If an object moves in a circle at a constant speed, its velocity vector will be constant.
false
For a projectile, which velocity remains constant as long as air resistance is ignored?
Total Velocity
Horizontal
Vertical
Velocity is constantly changing
Horizontal velocity
A ball was spinning around on a string of a certain radius at a constant speed. Then it went around the same curve at half of the original speed. Which of the following correctly identifies the new force acting on the ball?
The new force exerted on the ball towards the center of the curve was four times as much as before
The new force exerted on the car towards the center of the curve was one-half as much as before
The new force exerted on the ball towards the center of the curve was two times as much as before
The new force exerted on the car towards the center of the curve was one-fourth as much as before
The new force exerted on the car towards the center of the curve was one-half as much as before
Which of the following statements are true about momentum?
A.Momentum is a vector quantity.
B. The standard unit on momentum is the Joule. .An object with mass will have momentum.
D. An object which is moving at a constant speed has momentum.
A. momentum is a vector quantity
a boy is watching his grandfather fire an old cannon. he noticed that whenever the cannon is fired it moves with a very high velocity to the right. he also noticed when the cannon ball was fired the cannon ball moved very slowly to the left. how does conservation of momentum explain these observations?
A. The total momentum of the system was zero before the cannon was fired, so the cannonball and cannon must have equal and opposite momentum. Since the cannon has much more mass, it will have a smaller velocity.
B .The cannon gave momentum to the cannon ball, so they both begin to move. Since the cannon has much more mass, it will have a smaller momentum.
C. Since the motions of the cannon and cannon ball were caused by the same event, they must have equal and opposite momentum. Since the cannon has much more mass, it will have a larger velocity.
D. The cannon gave momentum to the cannon ball, so they both began to move. Since the cannonball has much less mass, it wit have a smaller momentum.
D. The cannon gave momentum to the cannon ball, so they both began to move. Since the cannonball has much less mass, it wit have a smaller momentum.
Which of the following represents a negative displacement?
Question 3 options:
An object moving forward
An object moving backward
An object at rest
An object changing direction
an object moving backwards
Which of the following is an example of two-dimensional motion with constant acceleration?
A car moving on a straight road
A ball thrown at an angle
A pendulum swinging back and forth
A rocket launching into space
a rocket launching into space
A man is whirling a 0.5 kg ball on a 1.0 m long string at 2 m/s. What is true about the force on the ball?
It pushes out, away from the center of the circle
It pulls in, toward the center of the circle
It pushes forward, tangent to the circle
There is no force on the ball
it pulls in towards the center of the circle
A 15-kg medicine ball is thrown at a velocity of 20 km/hr to a 60-kg person who is at rest on ice. The person catches the ball and subsequently slides with the ball across the ice. Determine the velocity of the person and the ball after the collision.
4km/h
A 2kg box slides down a ramp a distance of two meters before it reaches the ground. The ramp has an angle of 30o. The coefficient of kinetic friction for the ramp is 0.1.
What is the work done by gravity on the box?
Possible Answers:
35J
40J
10J
20J
20j
If an object has a constant velocity, what can be said about its acceleration?
Question 2 options:
The acceleration is zero
The acceleration is constant
The acceleration is increasing
The acceleration is decreasing
the acceleration is zero
Helen is parasailing. She sits in a seat harness which is attached by a tow rope to a speedboat. The rope makes an angle of 51° with the horizontal and has a tension of 350 N. Determine the horizontal and vertical components of the tension force.
220 N
and : 270 N
What is true about the Forces and acceleration on each
5000kg truck exerts a greater force on the 1000kg car, but the acceleration will be same.
5000kg truck exerts a greater force on the 1000kg car, but the 5000kg truck will get a greater acceleration.
Since they are moving with a constant velocity, the Forces on each of them are equal. But the 1000kg car will have greater acceleration since it has less mass.
Both Forces and acceleration are equal
Both Forces and acceleration are equal
A golf club has 10 kg m/s of momentum when it hits a golf ball that is at rest. After the collision, the golf club has a momentum of 1 kg m/s and the golf ball has a momentum of 9 kg m/s. Which of the following comparisons is TRUE about the change in momentum of the two objects?
the change in momentum is equal and opposite for the two objects
While training for breeding season, a 380 gram male squirrel does 32 pushups in a minute, displacing its center of mass by a distance of 8.5 cm for each pushup. Determine the total work done on the squirrel while moving upward (32 times).
10.13j
What is the difference between speed and velocity?
Speed is a scalar quantity, while velocity is a vector quantity
Speed is measured in meters per second, while velocity is measured in meters
Speed represents the total distance covered, while velocity represents the change in position
Speed is always positive, while velocity can be negative or positive
Speed represents the total distance covered, while velocity represents the change in position
Hector is walking his dog (Fido) around the neighborhood. Upon arriving at Fidella's house (a friend of Fido's), Fido turns part mule and refuses to continue on the walk. Hector yanks on the chain with a 67.0 N force at an angle of 30.0° above the horizontal. Determine the horizontal and vertical components of the tension force.
Fx: 58.0 N
Fy: 33.5 N
.A 5000 kg truck and a 1000kg car are traveling at constant speeds and then collide. What is true about the Forces and acceleration on each?
5000 kg truck exerts a greater force on the 1000 kg car, but the acceleration will be the same.
5000 kg truck exerts a greater force on the 1000 kg car, but the 5000 kg truck will get a greater acceleration.
Since they are moving with a constant velocity, the Forces on each of them are equal. But the 1000kg car will have greater acceleration since it has less mass.
Both Forces and acceleration are different.
Since they are moving with a constant velocity, the Forces on each of them are equal. But the 1000kg car will have greater acceleration since it has less mass.
An object has a mass of 100 kg moving at 5 m/s. What is the linear momentum of the object?
500kg
Egg A is dropped from a height of 1m onto the floor. Egg B is dropped from a height of 1m into a bucket of water. Which statement correctly describes why Egg B does not break?
A, Egg B experiences greater force over a longer time
b.
Egg B experiences greater force over a shorter time
C. Egg B experiences less force over a longer time
D egg b experiences less force over a shorter time
C. Egg B experiences less force over a longer time