NEET2008PhysicsGravitationActual
The speed of earth's rotation about its axis is . Its speed is increased to x times to make the effective acceleration due to gravity equal to zero at the equator. Then x is
Options
- A1
- B8.5
- C17
- D34
Correct answer
C. 17
Step-by-step solution
Earth rotates about its own axis in 24 h . So, T=24 60 60 ~s So, angular speed of earth about its own axis = 2 T = 2 24 60 60 rad / s At equator, g^ =g-R_e ^ 2 or 0=g-R_e ^ 2 or ^ = g R_e = 2 84.6 60 ^ = 24 60 60 84.6 60 17 ^ =17 So, value of x is 17 .