MCQ
A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to:
- A$\text{t}^{\frac{1}{2}}$
- B$\text{t}$
- C$\text{t}^\frac{3}{2}$
- D$\text{t}^2$
✓
Answer
- t.
Solution:
From,
V = u + at
V = 0 + at = at
As power, P = F × V
$\therefore$ P = (ma) × at = ma2t
As m and a are constants, therefore, $\text{P}\propto\text{t}$
Hence, right choice is (ii) t.
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