- Home
- Standard 11
- Physics
7.Gravitation
medium
The radius of the earth is $6400\, km$ and $g = 10\,m/{\sec ^2}$. In order that a body of $5 \,kg$ weighs zero at the equator, the angular speed of the earth is
A
$1/80\, radian/sec$
B
$1/400 \,radian/sec$
C
$1/800\, radian/sec$
D
$1/1600\, radian/sec$
Solution
(c) For the condition of weightlessness at equator $\omega = \sqrt {\frac{g}{R}} $
$\omega = \sqrt {\frac{1}{{640 \times {{10}^3}}}} = \frac{1}{{800}} \,rad/s$
Standard 11
Physics
