A wheel makes 180 revolutions in 1 minute

Given that Number of revolutions per minute = 180

Then per second, it will be $=180 / 60=3$

We know that In one complete revolution, the wheel turns at an angle of $2 \pi_{\text {rad. }}$

Then for 3 complete revolutions, it will take $3 \times 2 \pi=6 \pi$ radians.