Question

70. Angle of Revolution. Through how many radians does the minute hand of a wrist-watch rotate from 12:40 P.M. to 1:30 P.M.​

Answer 1

Answer:

$\frac{5\pi}{3}\:\mathrm{radians}$

Step-by-step explanation:

Each complete revolution of a circle is equal to $2\pi$ radians. The minute-hand travels one of these revolutions in 60 minutes. Since there are 50 minutes from 12:40 PM to 1:30 PM, the minute hand travels $\frac{50}{60}\cdot 2\pi=\frac{100}{60}\cdot 2\pi=\boxed{5\pi/3\:\mathrm{radians}}$