Helmet+or+Not

In 1992, only about 20% of adults and 5% of children wore protective helmets while bicycling.

suppose a person falls from a bicycle are rest. let d(t) be the distance (in feet) an average height person's head is from the ground when sitting on a bicycle (estimate or measure this distance). Use the Function based on gravity; use the equation to estimate the time it takes for a persons head to hit the ground d(t)=16t2

d(t)=5.67 d(t)=16t2

5.67=16t2

it occurs when t=.6 seconds



The function v(t)=32t gives the v(t) in feet per second of an object that falls for t seconds. Estimate the speed at which the head of an average height person hits the ground. The guy feel.

V(.6)=32(.6) v=19.2 feet per second

A cyclst not wearing a helmet will generally have lasting brain damage if the cyclist's head hits the ground at more than 18ft/s. based on the estimate from the 2nd problem, do you think that wearing a helmet is a good idea? yes, because you are going at a speed of at least 18 feet per second. if you crash, you could do serious damage to yourself .