What is the max speed w/ which a 1050 kg car can round a turn of radius 77m on a flat road if the coefficient of static friction betweentires and road is .80? Is this result independent of the mass of the car? Please answer and show work. :-)
2006-11-16 06:35:36 · 2 answers · asked by JitterBug589 3 in Science & Mathematics ➔ Physics
Let the speed of the car be v. The centripetal force for the car to go in a circle is provided by the friction in this case. That is
Frictional force = m*v^2 / r
If this works out greater than the max static frictional force, the car will skid. Hence the max. speed is given by
m*v^2 / r = Us*m*g
v = sqrt ( Us*r*g) = sqrt ( 0.8*77*10) = 24.8 m/s
From the above equation for v it is clear that the max speed is independent of the mass.
2006-11-16 07:34:33 · answer #1 · answered by muten 2 · 1⤊ 0⤋
I think the data is incomplete. In this case there are three forces acting on the car. First-m*V^2/r the centrifugal force acting at the cg, Second- the weight of the car m*g acting at the Center of Gravity of the car vertically down, Third- the frictional force acting at the contact point of the Tyre's and perpendicular to both the above forces. For the stability of the car it is necessary that the resultant of all these forces has to act between the middle third of the wheel base.Please note the base dimensions are not given with out which it is not possible to compute the restoring moment.
2006-11-16 15:08:19 · answer #2 · answered by openpsychy 6 · 0⤊ 0⤋