Posted by Ashley on .
A person who weighs 506 N is riding a 94N mountain bike. Suppose the entire weight of the rider plus bike is supported equally by the two tires. If the gauge pressure in each tire is 6.70 x 105 Pa, what is the area of contact between each tire and the ground?

Physics 
drwls,
(total Contact area)x(Gauge pressure)
= 2*(single tire Contact Area)x6.70*10^5 N/m^2
= Total wt.
= 600 N
Contact area = 4.48*10^4 m^2
= 4.48 cm^2 
Physics 
Name,
P = F/A
But there are two tires. So the weight will be supported by the two tires, thus two areas.
So P=F/2A, solving this,
A = F/2P
A = 600/2*6.7*10^5