Question

A runner completes the 200-meter dash with a time of 19.80 seconds. What was the runner's average speed in miles per hour?

Answer 1

The runner's average speed over a 200-meter dash completed in 19.80 seconds is 22.6 miles per hour, after converting from meters to miles and from seconds to hours.

Step-by-step explanation:

A runner who completes the 200-meter dash in 19.80 seconds would have an average speed given by the formula speed = distance/time. First, we need to convert the distance from meters to miles and the time from seconds to hours. There are 1609.34 meters in a mile and 3600 seconds in an hour.

Using the conversion factors, the distance in miles is 200 meters * (1 mile/1609.34 meters) = 0.1243 miles. The time in hours is 19.80 seconds * (1 hour/3600 seconds) = 0.0055 hours.

The runner's average speed in miles per hour (mph) can then be calculated as:
Speed = 0.1243 miles / 0.0055 hours = 22.6 mph.

This speed can be compared to the world record set by Usain Bolt in 2009, where his average running rate was 23.4 mph. The calculation above assumes constant velocity throughout the 200-meter dash.

Answer 2

v = 22.54 mph.

Step-by-step explanation:

Given that,

Distance moved, d = 200 m

Time, t = 19.8 s

We need to find the runner's average speed.

We know that,

1 mile = 1609.34 m

200 m = 0.124 miles

19.8 seconds = 0.0055 h

So,

Speed = distance/time

`v=(0.124)/(0.0055)\\\\v=22.54\ mph`

So, the runner's average speed is 22.54 mph.