Question

Which of the following statements are true? For a particle on the surface of the earth:

• A. the linear speed is minimum at the equator
• B. the angular speed is maximum at the equator
• C. the linear speed is minimum at the poles
• D. the angular speed is $7.3\times {10}^{-5}rad$ $s^{-1}$ at the equator

Answer 1

Answer: (C), (D)

The correct options are
C the linear speed is minimum at the poles
D the angular speed is $7.3\times {10}^{-5}rad$ $s^{-1}$ at the equator

Linear speed is $v=r\omega$.

At the equator,the radius of the earth r is maximum.

Therefore $\omega =\frac{v}{r}$ is minimum.

Also $\omega =\frac{2\pi }{T}=\frac{2\times 3.14}{24\times 60\times 60}=7.3\times {10}^{-5}rad{s}^{-1}$

Hence,the correct choices are C and D.