Question

A sprinter set a high school record in track and field, running 200.0 m in 21.7 s . What is the average speed of the sprinter in kilometers per hour?

Answer 1

Given data:

Distance travelled (d)= 200.0 m

Time taken (t) = 21.7 s

To determine:

The average speed in km/hr

Calculation:

Convert distance from m to km

1000 m = 1 km

200.0 m = 1 km * 200.0 m/1000 m = 0.2 km

Convert time from sec to hours

3600 sec = 1 hour

21.7 sec = 1 hour * 21.7 sec/3600 sec = 6.027 *10^-3 hrs

Speed is defined as the amount of distance travelled per unit time

Speed = distance/time = 0.2 km/6.027*10^-3 hr

           = 33.18 km/hr (or 33.2 km/hr)