Question

A student runs 100 meters in 11 seconds. What is the speed of the student? (2 points) speed = distance over time ; 1 mile = 1609 meters

Answer 1

The equation for speed is:

`S =(d)/(t)`

The student ran 100 meters in 11 seconds. Our distance is 100 meters and our time is 11 seconds.

`S =(100m)/(11s)`

When we solve we get the following:

`S = 9.09m/s`

I am guessing since you were given the unit conversion of 1 mile = 1609 meters, you need to answer in miles per hour. If you do, you will need to use dimensional analysis:

`(9.09m/s)/(1) *(1mi)/(1609m)  *(3600s)/(1hr)  =(32724mi)/(1609hr)  = 20.34mi/hr`

All of the units except miles and hour cancel out, which makes this problem valid. Your answer in mph (mi/hr) would be:

20.34 miles per hour