Worksheet discussion

  Welcome back to Wonders of Physics!!! On my previous physics class we discussed a worksheet that was assigned a couple days before this class. Our discussion focused mainly on question D.

Question D) Are there velocities equal at any time? How do you know?

Original answer: their velocities are equal at the 5 second mark.

Correct Answer: their velocities are never equal. On the graph, it states that the two cyclists are passing each other on the 5 second mark, but they do not have the same velocity.

Steps to figuring  out the answer:

1) Define velocity.
Velocity: speed in a given/certain direction

2) Answer the first part of the question. Are their velocities equal at any time?
No, their velocities are never equal.   

3) Answer the second question. How do you know?
Since this is a position vs. time graph we can infer that the slope of this graph is velocity. The two lines on the graph do not have the same slope, so they do not have the same velocity.

What did I learn?

Position vs Time graph= velocity slope
Velocity: Speed in a certain direction.