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$\text{t}^{\frac{1}{2}}$
- ✓$\text{t}$
- C$\text{t}^\frac{3}{2}$
- D$\text{t}^2$
✓
Answer
Correct option: B.
$\text{t}$
From,
$V = u + at$
$V = 0 + at = at$
As power, $P = F \times V$
$\therefore P = (ma) \times at = ma^2t$
As m and a are constants, therefore, $\text{P}\propto\text{t}$
Hence, right choice is $(ii)\ t.$
$V = u + at$
$V = 0 + at = at$
As power, $P = F \times V$
$\therefore P = (ma) \times at = ma^2t$
As m and a are constants, therefore, $\text{P}\propto\text{t}$
Hence, right choice is $(ii)\ t.$
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