MCQ
A stone of mass $0.3\,kg$ attached to a $1.5\,m$ long string is whirled around in a horizontal circle at a speed of $6\,m s ^{-1}$. The tension in the string is $............\,N$
- A$10$
- B$20$
- ✓$7.2$
- D$30$
✓
Answer
Correct option: C.
$7.2$
c
(c)
(c)
The force of tension in the string provides required centripetal force to keep the stone in circular motion.
$\therefore T=\frac{m v^2}{R}=\frac{0.3 \times(6)^2}{1.5}=7.2\,N$
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