An elevator starts on the ground floor and stops on the $10\mathrm{th}$ floor of a high-rise building. The elevator reaches a constant speed by the time it reaches the $1\mathrm{st}$floor and decelerates to rest between the $9\mathrm{th}$ and $10\mathrm{th}$floors. Describe the energy transformations taking place between the $1\mathrm{st}$ and $9\mathrm{th}$ floors.

A mass $m$ of $4.0 \mathrm{kg}$ slides down a frictionless incline of $\theta ={30}^{°}$ to the horizontal. The mass starts from rest from a height of $20 \mathrm{m}$.

Sketch a graph of the kinetic and potential energies of the mass as a function of time.

A mass $m$ of $4.0 \mathrm{kg}$ slides down a frictionless incline of $\theta ={30}^{°}$ to the horizontal. The mass starts from rest from a height of $20 \mathrm{m}$.

Sketch a graph of kinetic energy and potential energies of the mass as a function of distance travelled along the incline.

A mass $m$ of $4.0 \mathrm{kg}$ slides down a frictionless incline of $\theta ={30}^{°}$ to the horizontal. The mass starts from rest from a height of $20 \mathrm{m}$.

On each graph, sketch the sum of the potential and kinetic energies.

A mass $m$ is being pulled up an inclined plane of angle $\theta$ by a rope along the plane.

Find is the tension in the rope if the mass moves up at constant speed $v$.

A mass $m$ is being pulled up an inclined plane of angle $\theta$ by a rope along the plane.

Calculate is the work done by the tension when the mass is moves up a distance of $d \mathrm{m}$ along the plane.

A mass $m$ is being pulled up an inclined plane of angle $\theta$ by a rope along the plane.

Find is the work done by the weight of the mass.

A mass $m$ is being pulled up an inclined plane of angle $\theta$ by a rope along the plane.

Find is the work done by the normal reaction force on the mass.

A mass $m$ is being pulled up an inclined plane of angle $\theta$ by a rope along the plane.

What is the net work done on the mass $?$