Work Power Energy

Consider a force $\vec{F}=-x\hat{i}+y\hat{j}$ . The work done by this force in moving a particle from point $A\left(1,0\right)$ to $B\left(0,1\right)$ along the line segment is : (all quantities are in SI units)

A car of weight W is on an inclined road that rises by 100 m over a distance of 1km and applies a constant frictional force $\frac{W}{20}$ on the car. While moving uphill on the road at a speed of $10ms^{-1}$ , the car…

An engine is attached to a wagon through a shock absorber of length $1.5m.$The system with a total mass of $40,000\mathrm{kg}$ is moving with a speed of $72\mathrm{km}h^{-1}$ when the brakes are applied to bring it to…

A $0.4\mathrm{kg}$ mass takes $8s$ to reach ground when dropped from a certain height $P$above surface of earth. The loss of potential energy in the last second of fall is ______$J$. [Take$g=10ms^{-2}$]

To maintain a speed of $80\mathrm{km}h^{-1}$ by a bus of mass $500\mathrm{kg}$ on a plane rough road for $4\mathrm{km}$ distance, the work done by the engine of the bus will be _____$\mathrm{kJ}$. [The coefficient of…

A smooth inclined plane ends in a vertical circular loop, as shown in the figure. A small body is released from height $h$ as shown. If the body exerts a force of three times its weight on the plane at the highest point…

A block of mass 25 kg is pulled along a horizontal surface by a force at an angle $45^{\circ}$ with the horizontal. The friction coefficient between the block and the surface is 0.25. The displacement of 5 m of the…

A body of mass ' \(m\) ' connected to a massless and unstretchable string goes in verticle circle of radius ' \(R\) 'under gravity \(g\). The other end of the string is fixed at the center of circle. If velocity at top…

A body of mass 100 g is moving in circular path of radius 2 m on vertical plane as shown in figure. The velocity of the body at point $A$ is $10 \mathrm{~m} / \mathrm{s}$. The ratio of its kinetic energies at point $B$…

In the given figure, the block of mass$m$is dropped from the point$'A'$. The expression for kinetic energy of block when it reaches point$'B'$ is

A stone of mass$m$, tied to a string is being whirled in a vertical circle with a uniform speed. The tension in the string is

A block moving horizontally on a smooth surface with a speed of$40ms^{-1}$splits into two parts with masses in the ratio of$1:2.$ If the smaller part moves at$60ms^{-1}$in the same direction, then the fractional change…