Question

The shaft on an engine turns through an angle of 21 rad.

a) How many revolutions does the shaft make?

____rev

(b) What is this angle in degrees?

____°

Answer 1

Remember:

1 rev = 2 rad = 360 deg

1 rad = 57.2958 deg

Part A.

Given that engine turns 21 rad, So

21 rad = (21 rad)*(1 rev/(2 rad))

21 rad = 21/(2*pi) = 3.34 rev

Part B.

21 rad = (21 rad)*(57.2958 deg/1 rad)

21 rad = 1203.21 deg

Please Upvote.