Question

A thread is being pulled off a spool at the rate of 57.3 cm per sec. Find the radius of the spool if it makes 141 revolutions per min. Round to two decimal places as needed.

Answer 1

Answer: r= 0.04meter

Explanation:

The velocity V and angular speed w is related to the radio by

V=w*r

r=V/w

But the standard unit for velocity is m/s so we convert 57.3cm/sec to m/s

57.3/100= 0.57m/s

Also Angular speed w is rad/secs

So we convert rev/min to rad/sec

0.1rad/sec equals 1 rev/mins

141rev/mins * 0.1rad/secs

=14.1rad/sec

r = V/w

= 0.573/14.1

= 0.04m to 2d.p