Work Questions

As per this diagram a point charge +q is placed at the origin O. Work done in taking another point charge - Q from the point A [co-ordinates (0, a)] to another point B [co-ordinates (a, 0)] along the straight path AB is :

A force F acting on an object varies with distance x as shown here. The force is in N and x is in m. The work done by the force in moving the object from x = 0 to x = 6 m is :

The potential energy of a long spring when stretched by $2\text{cm}$ is $U$. If the spring is stretched by $8\text{cm}$ the potential energy stored in it is :

A body of mass $3\text{kg}$ is under a constant force which causes a displacement $s$ in metres in it, given by the relation $s=\frac{1}{3}{t}^2$, where $t$ is in sec. Work done by the force in $2\text{sec}$ is :

$300\text{J}$ of work is done in sliding a $2\text{kg}$ block up an inclined plane of height $10\text{m}$. Taking $g=10{\text{m/s}}^2$, work done against friction is :