Question

I do not understand Part B.

The crankshaft in a race car goes from rest to 3600 rpm in 2.1 s. What is the crankshaft's angular acceleration? Express your answer using two significant figures. Alfa= 180 rad/s^2 How many revolutions does it make while reaching 3600 rpm? Express your answer using two significant figures.

Answer 1

here,

the rotational speed , w = 3600 rpm

w = 376.8 rad/s

time t = 2.1 s

B)

from part a)

alpha = 180 rad/s^2

let the angle be theta

theta = u0*t + 0.5 * alpha * t^2

theta = 0 + 0.5 * 180 * 2.1^2

theta = 396.9 rad

n = theta/2pi = 63.2 revolution

the number of revolutions are 63.2