MCQ
When a body moves in a circular path, no work is done by the force since
- Athere is no net force
- Bthere is no displacement
- Cforce is always away from the centre
- ✓force and displacement are perpendicular to each other
✓
Answer
Correct option: D.
force and displacement are perpendicular to each other
d
The radial force and displacement are normal to each other in circular motion.
The radial force and displacement are normal to each other in circular motion.
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$(A)$ $2.76 \times 10^{-46} \mathrm{~kg} \mathrm{~m}^2$ $(B)$ $1.87 \times 10^{-46} \mathrm{~kg} \mathrm{~m}^2$
$(C)$ $4.67 \times 10^{-47} \mathrm{~kg} \mathrm{~m}^2$ $(D)$ $1.17 \times 10^{-47} \mathrm{~kg} \mathrm{~m}^2$
$3.$ In a $\mathrm{CO}$ molecule, the distance between $\mathrm{C}$ (mass $=12$ a.m.u) and $\mathrm{O}$ (mass $=16$ a.m.u.), where $1$ a.m.u. $=\frac{5}{3} \times 10^{-27} \mathrm{~kg}$, is close to
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