JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A mass of \(1\text{ kg}\) is kept on an inclined plane with \(30°\) inclination with respect to horizontal plane and it is at rest initially. Then the whole assembly is moved up with constant velocity of \(4\text{ m/s}\). The work done by the frictional force in time \(2\text{ s}\) is _______ J. (Take \(g = 10\text{ m/s}^2\))
- A \(20\)
- B \(25\)
- C \(30\)
- D \(10\)
Answer & Solution
Correct Answer
(A) \(20\)
Step-by-step Solution
Detailed explanation
Since the assembly moves with a constant velocity, the acceleration of the mass is zero. The mass is in equilibrium relative to the incline. The frictional force \(f\) acting on the mass balances the component of gravity along the inclined plane. Therefore, the magnitude of the…
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