MCQ
The angular velocity of the earth at present in $\omega $ . With what angular velocity should it rotate so that weight of body at the equator appears to be zero ? ....... $\omega $
- A$2$
- B$8$
- ✓$17$
- D$289$
✓
Answer
Correct option: C.
$17$
c
The present value of angular velocity
The present value of angular velocity
$=\frac{2 \pi}{86400}=1.2 \times 10^{-3}$ rad/sec. $A$ body at
equator appears weightless if weight provides centripetal force,
i.e., $m \omega^{2} r=m g$
Or $\omega=\sqrt{\frac{g}{r}}=\sqrt{\frac{9.8}{6.4 \times 10^{6}}}$ rad/sec.
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