JAMB Physics 2015 Paper

Concept:Angular velocity measures how fast an object rotates around a circular path. It is related to the linear speed and the radius of the circle.Explanation:The relationship between linear speed $v$, radius $r$, and angular velocity $\omega$ is:$$v = \omega r$$Rearranging to find angular velocity:$$\omega = \frac{v}{r}$$Given: $v = 2\ \mathrm{m/s}$ and $r = 0.7\ \mathrm{m}$.Substitute the values:$$\omega = \frac{2}{0.7}$$$$\omega = 2.857\ \mathrm{rad/s}$$Rounding to the nearest whole number gives:$$\omega \approx 3\ \mathrm{rad/s}$$The mass of $3\ \mathrm{kg}$ is not needed because angular velocity depends only on speed and radius in this case.Answer:The angular velocity is approximately $3\ \mathrm{rad\,s^{-1}}$.