Ch 4 Linear Motion

Physics

Ch 4 – Linear Motion

Pre-Test

1. If an object has an acceleration of 0 m/s2, it means the object is…
2. Not moving
3. Not changing position
4. Not changing velocity
5. Moving with constant speed
6. Not experiencing any forces

1. If car A passes car B, then car A must be
2. accelerating
3. accelerating at a higher rate than car B
4. moving faster than car B and accelerating at a higher rate than car B
5. moving faster than car B but not necessarily accelerating

1. A football player is running down the football field in a straight line. He starts at the 0-yard line at 0 seconds. At 1 second, he is on the 10-yard line; at 2 seconds, he is on the 20-yard line; at 3 seconds, he is on the 30-yard line; and at 4 seconds, he is on the 40-yard line. This is evidence that he is

1. Accelerating
2. Covering greater and greater distance in each consecutive second.
3. In a state of dynamic equilibrium.
4. Covering less and less distance in each consecutive second

1. As an object freely falls
2. Its speed increases
3. Its acceleration increases
4. Both a and b
5. None of the above

1. A ball is thrown straight up into the air. At the peak of its flight
2. The speed is zero and the acceleration is zero
3. The speed is zero and the acceleration is 9.8 m/s2 downward
4. The speed is zero and the acceleration is 9.8 m/s2 upwards
5. The speed is 9.8 m/s2 and the acceleration is zero

1. Ten seconds after being dropped from rest, the speed of a freely falling object will be
2. About 10 m/s b. About 50 m/sc. About 100 m/sd. Greater than 100 m/s

1. Lee Kingoyle is driving her car down Rte 43 leaving a trail of oil drops on the road way. If you started watching Lee from the spot marked with an X until the car reached the position shown, what can you say about her velocity and acceleration?

X ...... …

1. Velocity is to the right, acceleration is to the right
2. Velocity is to the right, acceleration is to the left
3. Velocity is to the right, acceleration is zero
4. Velocity is to the left, acceleration is to the right
5. Velocity is to the left, acceleration is to the left

1. A snowmobile is traveling at some constant non-zero speed for a short time. The brakes are then applied uniformly accelerating the snowmobile in a direction opposite of its motion causing it to slow down to a stop. The snowmobile then remains at rest for the remainder of the time in question. Sketch a distance vs. time graph that corresponds to this description of motion.

1. Describe the motion represented by the following speed vs. time graph:

1. A ball is thrown vertically upward.
2. Describe the ball’s velocity while it is on its way up, at the peak, and on the way down.

1. Describe the ball’s acceleration while it is on its way up, at the peak, and on the way down.

1. Differentiate between speed and velocity.

1. Two children are playing with bouncy balls. One child simply drops ball A from rest. The other child throws ball B straight downward with a speed of 15 m/s. Compare the accelerations of the two balls while they are in flight towards the ground (air resistance is negligible).

1. An African swallow can travel with an average speed of about 11 m/s. How long would it take the swallow to go 1.6 x 104 m?

1. An apple falls from a tree striking the ground in 1.5 s. How fast is the apple moving when it hits the ground? How high did the apple fall from?