Question

A sprinter set a high school record in track and field, running 200.0 m in 21.9 s. What is the average speed of the sprinter in kilometers per hour?

Answer 1

Answer:- The average speed of sprinter is $32.9\frac{km}{hour}$ .

Solution:- From given data, distance covered by the sprinter is 200.0 m and it takes 21.9 seconds. We know that:

$speed=\frac{distance}{time}$

Let's plug in the values and calculate the speed.

$speed=\frac{200.0m}{21.9sec}$

$speed=9.13\frac{m}{sec}$

It wants speed in kilometer per hour. So, let's do the unit conversion as:

1000 m = 1 km

60 sec = 1 min

60 min = 1 hour

The set up looks as:

$9.13\frac{m}{sec}(\frac{1km}{1000m})(\frac{60sec}{1min})(\frac{60min}{1hour})$

= $32.9\frac{km}{hour}$

So, the average speed of the sprinter is $32.9\frac{km}{hour}$ .