Question

In 2009, usain bolt of jamaica set a world record of 9.58 s in the 100-m dash. what was his average speed? give your answer in kilometers per hour.

Answer 1

Usain Bolt's average speed for his world record 100-m dash in 2009 was 37.58 km/h, calculated by converting the 100 meters to kilometers and then dividing by the time, with a further conversion to hours.

Step-by-step explanation:

To calculate Usain Bolt's average speed during his 2009 world record 100-m dash, we can use the formula for average speed, which is total distance divided by total time.

Firstly, convert the distance from meters to kilometers: 100 meters = 0.1 kilometers.

Then, calculate the average speed: Average Speed = Distance / Time = 0.1 km / 9.58 s.

Since we want the output in kilometers per hour (km/h), we need to convert seconds to hours. There are 3600 seconds in an hour, so we multiply the speed by 3600 to convert it to km/h:

Average Speed = (0.1 km / 9.58 s) * 3600 s/h = 37.5779 km/h

Round the answer to two decimal places, Usain Bolt's average speed was 37.58 km/h.

Answer 2

Using a calculator, we find that Usain Bolt's average speed over the 100 meter race was about 23.2 miles per hour. Note that some of the numbers in this calculation, namely 100, 3600, and 5280 are exact while 3.28 and 9.63 are only approximate. Since the approximate numbers only have 3 significant digits we only report three digits in the final answer.