MCQ
A body of mass $2 \,kg $ collides with a wall with speed $100\, m/s$ and rebounds with same speed. If the time of contact was $1/50 \,second$, the force exerted on the wall is
- A$8 \,N$
- ✓$2 \times {10^4}\,N$
- C$4\, N$
- D${10^4}\,N$
✓
Answer
Correct option: B.
$2 \times {10^4}\,N$
b
(b)$F = \frac{{dp}}{{dt}} = m\frac{{dv}}{{dt}} = \frac{{m \times 2v}}{{1/50}}$= $\frac{{2 \times 2 \times 100}}{{1/50}} = 2 \times {10^4}N$
(b)$F = \frac{{dp}}{{dt}} = m\frac{{dv}}{{dt}} = \frac{{m \times 2v}}{{1/50}}$= $\frac{{2 \times 2 \times 100}}{{1/50}} = 2 \times {10^4}N$
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