Mechanical Energy

Derive that mechanical energy is always constant in the case of a freely falling body.

An object has zero mechanical energy and non-zero momentum. Is it possible? Explain with examples.

The potential energy of a freely falling object changes continuously. How? Does it violate the law of energy conservation? Explain.

Prove that for a freely falling object, the sum of its potential energy and kinetic energy remains unchanged at all points during its fall.

Give reason for the following : The kinetic energy of a freely falling object increases, yet it holds law of conservation of energy.

Mechanical energy of an object is zero. Can it possess momentum? Can an object having zero momentum possess mechanical energy? Give example to support the situation in case it is true.

Which type of energy is produced due to motion and due to the position of an object?

The _____ energy is consists of kinetic energy and potential energy.

 _____ energy is used during football playing.

The primary source of energy is _____ .

An aeroplane flying at a height of $50 \mathrm{km}$ has _____.

Ability to do work is -

If an object of mass $50 \mathrm{kg}$ is lifted to height of $3 \mathrm{m}$ then find its potential energy. If this object falls freely from that height then find its kinetic energy when it is at halfway distance. $\left(\mathrm{g}=10 \mathrm{m}/{\mathrm{s}}^2\right)$

Prove that the mechanical energy of a free falling object (under gravitational field) remains constant at every point of motion.

An object falls freely from a height, and its potential energy is continuously decreasing. Explain how mechanical energy is conserved in this process?

What do you understand by conservation of mechanical energy?

The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy? Why?

Name the type of energy possessed by an aeroplane flying at an altitude.

The sum of the kinetic energy and potential energy of a body is called its _____.

From a building two balls $A$ to $B$ are thrown such that $A$ is thrown upwards and $B$ downwards (both vertically). If $v_A$ and $v_B$ are their respective velocities on reaching the ground, then