2) Angular Kinematics: An automobile engine slows down from 4500 rpm to 1200 rpm in 2.5 s. a) What is 4500 rpm in rad/s? HINT: rpm is revolutions per minute b) Calculate the average angular acceleration as the engine slows down c) The total number of revolutions the engine makes in this time. Hint: Determine number of radians rst. Potentially Useful Information angular displaceme nt At average angular ve locity = - time elapsed Aw a = average angular acceleration = change in angular ve locity At time elapsed final = Oinitial + @initial + + oct2 a centripeta = @ final = @initial + 20 (0 final - Oinitial x = re my final = @initial + at v = rw Fcentripeta r a = ra a = final + initial F = ma 2 circumference of a circle = 2xr s (arc length) = re Area of circle = nr where r is the radius, O is the angular position (radians), @ is the angular velocity (radians per second), a is the constant angular acceleration (radians per second per second). Acceleration due to gravity, g = 9.8 m/s2 towards the centre of the Earth K.E. = 4mv2 P.E= mgh Work = AKinetic Energy Fkineticfriction = UN Work = Force x distance (where Force and distance are co - linear) T= rx F Work Power = Time