Q194 / 200 · MHT CET - Medical 2026 (21 April Shift 1) · Physics
A man weighing 60 kg is standing in a lift. If the lift moves with an acceleration of $'x'$ $\text{m/s}^2$, the apparent weight of the man is 840 N. The acceleration $'x'$ of the lift is such that ( $g = 10\ \text{m/s}^2$ )
- Correct answerAThe lift ascends with an acceleration of 4 $\text{m/s}^2$
- BThe lift descends with an acceleration of 4 $\text{m/s}^2$
- CThe lift descends with an acceleration of 2 $\text{m/s}^2$
- DThe lift ascends with an acceleration of 2 $\text{m/s}^2$
Solution
Actual weight of the man, $W = mg = 60 \times 10 = 600$ N.
Since the apparent weight ($840$ N) is greater than the actual weight ($600$ N), the lift must be accelerating upwards.
Let the upward acceleration of the lift be $a$. The apparent weight is given by:
$W_{app} = m(g + a)$
$840 = 60(10 + a)$
$10 + a = 14$
$a = 4$ m/s$^2$
The lift ascends with an acceleration of $4$ m/s$^2$.
Answer: The lift ascends with an acceleration of 4 $\text{m/s}^2$
Since the apparent weight ($840$ N) is greater than the actual weight ($600$ N), the lift must be accelerating upwards.
Let the upward acceleration of the lift be $a$. The apparent weight is given by:
$W_{app} = m(g + a)$
$840 = 60(10 + a)$
$10 + a = 14$
$a = 4$ m/s$^2$
The lift ascends with an acceleration of $4$ m/s$^2$.
Answer: The lift ascends with an acceleration of 4 $\text{m/s}^2$
Hence, the correct answer is option: 'A'.