List of top Physics Questions on Power asked in JEE Main

A body of mass \(4\) kg is placed at a point \(P\) having coordinates \( (3,4) \) m. Under the action of force \( \mathbf{F} = (2\hat{i} + 3\hat{j}) \) N, it moves to a new point \(Q\) having coordinates \( (6,10) \) m in \(4\) sec. The average power and instantaneous power at the end of \(4\) sec are in the ratio:
A sand dropper drops sand of mass \( m(t) \) on a conveyor belt at a rate proportional to the square root of the speed \( v \) of the belt, i.e., \( \frac{dm}{dt} \propto \sqrt{v} \). If \( P \) is the power delivered to run the belt at constant speed, then which of the following relationships is true?
A body of mass \(4\) kg is placed at a point \(P\) having coordinates \( (3,4) \) m. Under the action of force \( \mathbf{F} = (2\hat{i} + 3\hat{j}) \) N, it moves to a new point \(Q\) having coordinates \( (6,10) \) m in \(4\) sec. The average power and instantaneous power at the end of \(4\) sec are in the ratio:
By what percentage will the illumination of the lamp decrease if the current drops by 20%?
A body of mass $2\, kg$ is initially at rest It starts moving unidirectionally under the influence of a source of constant power P Its displacement in $4 s$ is $\frac{1}{3} \alpha^2 \sqrt{P} m$ The value of $\alpha$ will be_______
From the given transfer characteristic of a transistor in CE configuration, the value of power gain of this configuration is 10x, for RB = 10 kΩ, and Rc = 1 kΩ. The value of x is_____.