Objective

To calculate the average speed of an object
To calculate the average velocity of an object.

Equipment.

Blank paper
Calculator (a calculator is located on the widget page)
Pen or pencil

Problem 1

A feather is dropped on the moon from a height of 1.40 meters. The acceleration of gravity on the moon is 1.67 m/s/s. Determine the time for the feather to fall to the surface of the moon.

Problem 2

If Michael Jordan has a vertical leap of 1.29 m, then what is his takeoff speed and his hang time (total time to move upwards to the peak and then return to the ground)?

Problem 3

A stone is dropped into a deep well and is heard to hit the water 3.41 s after being dropped. Determine the depth of the well (speed of sound is 340 m/s).

Problem 4

You are asked to do an experiment to measure g. You set up a device which drops a metal ball from rest from a height of 1.650m. Using an accurate timing device which detects the release of the ball and its landing on the floor, you measure the average time of the falling ball to be 0.585s.
a.What do you measure the value of g as?
b.Can you give an explanation as to the error from the accepted value of 9.8 meters per square second?

Problem 5

A person is stuck inside a falling elevator, whose cable broke 10 meters above the ground. Lets say the person wanted to cancel out their final velocity by jumping exactly when the elevator hits bottom. Assume the elevator started from rest.
a. How long after the cable breaks would the person need to jump?
b. In order to completely cancel their accumulated velocity, at what velocity (relative to the elevator) would they need to jump?
c. If they were to jump at this velocity on stable ground, how high would they go? Is this reasonable?

Problem 6

A ball is thrown straight up in the air and passes a certain window 0.30s after being released. It passes the same window on its way back down 1.50s later. What was the initial velocity of the ball?
external image constacc9.gif

Problem 7

A basketball is dropped from a height of 2.00 meters above the ground. On the first bounce the ball reaches a maximum height of 1.10 meters where it is caught. Find the velocity of the ball:
a. just before it makes contact with the ground
b. just after it leaves the ground after the bounce