# Homework Help: Strobe diagram

1. Jul 4, 2006

### uwmphysics

ok. I have to look at this strobe diagram of a ball (assuming it is moving from left to right)

o..........o........o......o....o..o.oo

Which statement best describes the motion of the ball shown in the strobe diagram below? (assume the ball moves from left to right)
The ball is
a. moving with constant speed
b. speeding up
c. accelerating
d. stopped

ok from left to right it is getting slower and coming to a stop. So my first thought was that the answer is stopped. Can somebody who knows how to read these diagrams tell me if they agree?

2. Jul 4, 2006

### Kurdt

Staff Emeritus
It is slowing down as you say so what describes is commonly known as the rate of change of speed?

3. Jul 4, 2006

### uwmphysics

accelerating-but can acceleration also be slowing down? our professor used the term decceleration but thats not listed, and its not stopped the whole time, which is why i had a hard time answering the question. Thank you!

4. Jul 4, 2006

### Kurdt

Staff Emeritus
Decelleration is just a term for saying the acceleration is slowing down the object rather than speeding up. Broadly speaking acceleration can mean an object is speeding up or slowing down and hence you have to have extra information to determine which such as saying decelleration.