Energy and It's Sources

Q.

Explain energy transformation with the help of examples?

Q.

An object of mass$m$ is dropped from the top of a tall building of height $h$. Two forces act on it during its fall: gravity and air resistance. The later is always directed against the motion and its magnitude is proportional to the speed of the object. The acceleration due to gravity is $g$. Which of the following statements is true about the motion of the object?

1. The object will fall throughout with uniform speed.

2. The object will fall throughout with uniform acceleration.

3. The sum of the kinetic energy and gravitational potential energy remains constant throughout the fall.

4. The maximum kinetic energy of the object will be less than $mgh$.

Q.

What is the percentage of heat loss from the skin?

Q.

Define the term Fuel.

Q.

Capacity to do work?