posted by bob on .
A runner times his speed around a circular track with a circumference of 0.508 mi. At the start he is running toward the east and the track starts bending toward the north. If he goes halfway around, he will be running toward the west. He finds that he has run a distance of 0.678 mi in 4.00 min.
i need to find average speed in m/s and average velocity in m/s at what direction from north.
average velocity=(velocityfinal -velocityinitial)/2
velocity final= .678/4 *direction of final run
what is the final direction? Well , he has ran .678mi, which is .678/.508 revolutions, or 1 and a third rev, or a final angle of 120 deg. He is sruning at a 90 degree angle to that.
Sketch this out, and if needed, I will critique your thinking. The results will surprise you.
i did not understand it. please solve it till the end