11.184 681 46 mile/hour (mph)
this is the site I used:
http://www.onlineconversion.com/speed_common.htm
Legally Carl Lewis.
A 12.5-second 100m equates to a time of 4.572 seconds in the 40-yard dash.
An average time for a 14-year-old running the 50 meter dash is around 9 seconds. For a 100 meter dash, it would be about 13 seconds.
Usain Bolt took 41 steps to set the new world record of 9.58 seconds
The men's world record in the 400 meter dash is 43.18 seconds. The men's world record in the 400 meter hurdles is 46.78 seconds. This is a difference of 3.60 seconds. The women's world record in the 400 meter dash is 47.60 seconds. The women's world record in the 400 meter hurdles is 52.34 seconds. This is a difference of 4.74 seconds.
A 12 year old's average time for the 100 meter dash, should be about 15 or 16 seconds.
His 5.0 40-meter dash translates to a time of 4.572 seconds in the 40-yard dash.
45 seconds.
Approximately 8 seconds
Florence Griffith-Joyner holds the women's world record in the 100 meter dash at 10.49 set in 1988.Florence Griffith-Joyner is the fastest female 100 m runner in the world. She set the record of 10.49 seconds on July 16, 1988.
The equivalent time for the 100 yards dash based on a 9.58 second 100 meter dash world record is approximately 10.44 seconds.
Usain Bolt. The Jamaican runner broke his own previous record of 9.72 seconds on the 16th of August 2008 during the Beijing Olympics at a remarkable 9.68 seconds.