Work by Constant Force — Prelims Questions

A block of mass $2\,\text{kg}$ is pulled by a constant force of $10\,\text{N}$ on a horizontal surface. The force makes an angle of $30^\circ$ with the horizontal. If the block is displaced by $5\,\text{m}$ horizontally, what is the work done by the applied force? (Given: $\cos 30^\circ = \frac{\sqrt{3}}{2} \approx 0.866$)

A porter lifts a luggage of $15\,\text{kg}$ from the ground and puts it on his head $1.5\,\text{m}$ above the ground. Calculate the work done by the porter on the luggage. (Take $g = 10\,\text{m/s}^2$)

A body moves a distance of $10\,\text{m}$ along a straight line under the action of a $5\,\text{N}$ force. If the work done is $25\,\text{J}$, what is the angle between the force and the direction of motion?

A force $\vec{F} = (2\hat{i} + 3\hat{j}),\text{N}$ acts on an object, causing a displacement $\vec{d} = (4\hat{i} - 2\hat{j}),\text{m}$. What is the work done by the force?

A person carries a $10\,\text{kg}$ suitcase on his head and travels a horizontal distance of $50\,\text{m}$ on a straight road. What is the work done by the person on the suitcase? (Assume constant velocity and $g = 10\,\text{m/s}^2$)

A $5\,\text{kg}$ block slides $2\,\text{m}$ down an inclined plane that makes an angle of $30^\circ$ with the horizontal. The coefficient of kinetic friction is $0.2$. Calculate the work done by the friction force. (Take $g = 10\,\text{m/s}^2$)