MCQ
Angular momentum of the particle rotating with a central force is constant due to
- Aconstant torque
- Bconstant force
- Cconstant linear momentum
- ✓zero torque
✓
Answer
Correct option: D.
zero torque
d
We known that $\overrightarrow {{\tau _c}} = \frac{{\overrightarrow {d{L_c}} }}{{dt}}$
We known that $\overrightarrow {{\tau _c}} = \frac{{\overrightarrow {d{L_c}} }}{{dt}}$
Where $\overrightarrow {{\tau _c}} $ torque about the center of mass of the body and $\overrightarrow {{L_c}} $ $=$ Angula momentum about the center of mass of the body. central forces act along the center of mass. Therefore torque about center of mass is zero.
When $\overrightarrow {{\tau _c}} $ $= 0$ then $\overrightarrow {{L_c}} $ $=$ constt.
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