posted by mymi .
A monster truck has tires with a diameter of 1.10 m and is traveling at 30.0 m/s. After the brakes are applied, the truck slows uniformly and is brought to rest after the tires rotate through 49.0 turns.
(a) What is the initial angular speed of the tires?
(b) What is the angular acceleration of the tires? (Enter the magnitude only.)
(c) What distance does the truck travel before coming to rest?
Given: D = 1.1m., V0 = 30m/s, 49rev.
C = pi*D = 3.14 * 1.1 = 3.46m. = Circumference of tirs.
a. Vo = 30m/s * 6.28rad/3.46m = 54.5rad/s.
b. d = 49rev * 3.46m/rev = 169.3m =
a = (Vf^2 - Vo^2) / 2d,
a = (0 - (30)^2) / 338.6 = -2.66m/s^2 =
a = -2.66m/s^2 * 6.28rad/3.46m =
-4.82rad/s^2. = Angular acceleration.
c. d = 49rev * 3.46m/rev = 169.3m.