Question

A went for a 10-km run and completed it in 65 minutes. She displaces from her start point by 2.9 km.

1. What was her average speed for her run?

2. Based on your intermediate answer for speed (not the final one with 3 sig figs) and given that her stride length is 0.67m, what would her approximate stride rate be (strides per second)?

Answer 1

we know that

average speed = (total distance) / (total time taken )

here given that ,

total distance = 10 km = 10000 m

total displacement = 2.9 km

total time = 65 minutes = 3900 seconds

1 ) so average speed = 10 km / 65 minute = 10000 m / 3900 s = 2.56 m/s

so  her average speed for her run = 2.56 m/s

2) stride length = 0.67 m

total no of strides = 10000/ 0.67 = 14925.37 strides

stride rate = no of stride / total time = 14925.37 strides /  3900 seconds = 3.83 strides per second