Find the coefficient of kinetic friction between the tires and the road
2006-10-24 15:55:22 · 2 answers · asked by Dan L 1 in Science & Mathematics ➔ Physics
This is a problem involving kinetic energy, work energy, and coefficient of kinetic friction.
KE of car=1/2mv^2, where KE is the kinetic energy given in J, m is the mass in kg, and v is the velocity in m/s.
Substitute given values:
KE=1/2*2400*25^2
=750,000N
Work=F*s, where Work is in J, F is the force applied in N, and s is the displacement in meters.
Substitute given values:
Work=F*50
Based on principle of conservation of energy:
KE=Work
750,000=F*50
F=750,000/50
=15000N
Coefficient of Kinetic friction, u:
F=uR, where F is the force of friction of 15,000N and R is the Normal to the road surface exerted by the weight of the car equal to 2400*9.8N.
Substitute given values:
15000=u2400*9.8
u=15000/2400*9.8
=0.638
2006-10-24 21:44:00 · answer #1 · answered by tul b 3 · 0⤊ 0⤋
force of friction = (u)(normal force)
u = rubber on asphalt (dry) = .67
normal force = 2400 x 25 = 60000
force of friction = (.67)(60,000)
force of friction = 40,200 N
2006-10-24 22:59:46 · answer #2 · answered by SideWinderGX 2 · 0⤊ 0⤋