A runner covers one lap of a circular track 40.0 m in diameter in 62.5s (a) for that lap what were her average speed and average velocity? (b) if she covered the first half lap in 28.7 s, what were her average speed and average velocity for that half lap?
Physics - bobpursley, Wednesday, June 3, 2009 at 1:02pm
I assume you know the distance around a circle (PI*diameter).
Physics - Sarah, Wednesday, June 3, 2009 at 1:10pm
what do you mean by final position - initial position
Physics - Damon, Wednesday, June 3, 2009 at 7:25pm
The final - initial positions in part b are on opposite sides of the circle. For distance run, you went half way around the track. (pi D/2)
For distance between beginning point and end point you do not go around the track, you draw a vector straight across from start to finish, thus just the diameter.(D)
In part a, your average velocity was ZERO, because your final position is the same as your initial position and you went nowhere. Of course your speed was pi D/62.5