JEE Mains · Physics · STD 11 - Work,energy,power and collision
- JEE Mains 2020
- Medium
- Numerical
An elevator in a building can carry a maximum of \(10\) persons, with the average mass of each person being \(68\; kg\). The mass of the elevator itself is \(920\; kg\) and it moves with a constant speed \(3\; \mathrm{m} / \mathrm{s}\). The frictional force opposing the motion is \(6000 \;\mathrm{N}\). If the elevator is moving up with its full capacity, the 10.Power delivered by the motor to the elevator \(\left(\mathrm{g}=10 \;\mathrm{m} / \mathrm{s}^{2}\right)\) must be at least .............. \(\mathrm{W}\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(66000\)
Step-by-step Solution
Detailed explanation
elevater moving with constant speed hence \(\mathrm{T}=6800+9200+6000\)
\(\mathrm{T}=22000 \mathrm{N}\)
10.Power \(=\mathrm{T} \cdot \mathrm{v}=22000 \times 3\)
\(=66000 \mathrm{W}\)
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