Energy

What will be the height of the body height if it has a mass of $3 \mathrm{kg}$ and after $8 \mathrm{seconds}$ it reaches the ground?

When you ride a bicycle, what are the many energy transfers that take place?

An electric heater is rated $1500 \mathrm{W}$. The energy used by it in $10$ hours is :

What is mechanical energy and its types?

The only type of potential energy is elastic potential energy.

Explain the types of potential energy.

Select the types of potential energy from the following:

Kinetic energy of a body can be increased more by _____.

A body of $12 \mathrm{kg}$ mass is placed at a certain height from the surface of earth. If its potential energy is $480 \mathrm{J}$, then what will be its height with respect to earth's surface? $(g=10 {\mathrm{ms}}^{-2})$

You burn a bulb of $100 \mathrm{W}$ daily for $5$ hours. What will be the energy spent in units by the bulb in one day?

A stone is thrown upwards as shown in the diagram. When it reaches P, the _____ energy of the stone will be maximum.
  

Gravitational potential energy is the energy stored when an object is lifted above the surface of the earth.

The energy possessed by an object when it reaches the bottom-most point during a free fall is _____ (potential/kinetic) energy.

Explain the energy conversion takes place in an object falling from a height.

The total energy of a body is conserved during free fall.

An object of mass $6 \mathrm{kg}$ falls from a height of $5 \mathrm{m}$. Find the change in its potential energy. ($\mathrm{g}=10 \mathrm{m} {\mathrm{s}}^{-2}$)

Calculate the work done in taking object of $1 \mathrm{kg}$ mass at $4 \mathrm{m}$ height? ($\mathrm{g}=10 \mathrm{m}/{\mathrm{s}}^2$)

An object of mass $40 \mathrm{kg}$ is raised to a height of $5 \mathrm{m}$ above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down.

A certain household has consumed $250$ units of energy during a month. How much energy is this in joules?

An old coolie carries heavy luggage on his head at railway station. Nishant watches it from a distance and reaches to help him out. He helps the coolie in placing the luggage at its place. The coolie thanks Nishant for his kindness. Nishant ask him to be careful in furture.
Read the above passage and answer the following questions:
 Give reason for your reply on the above question.