MCQ
A force acts on a block as shown in figure. Find time when block loses contact with surface.
- A$t = 25/3 \, \sec$
- ✓$t = 50/3 \, \sec$
- C$t = 100/3 \, \sec$
- D$t = 50 \, \sec$
✓
Answer
Correct option: B.
$t = 50/3 \, \sec$
b
$\mathrm{N}=\mathrm{F} \sin 37^{\circ}-\mathrm{mg}$
$\mathrm{N}=\mathrm{F} \sin 37^{\circ}-\mathrm{mg}$
as per given condition
When $\mathrm{N}=0 \quad \mathrm{F} \sin 37^{\circ}-\mathrm{mg}=0$
$\Rightarrow F \sin 37^{\circ}=\mathrm{mg}$
$\Rightarrow 10 t \times \frac{3}{5}=10 \times 10 \Rightarrow t=\frac{50}{3} \mathrm{s}$
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