Question

3. a)What is kinetic energy? b) What is potential energy? c) What is the law of conservation of energy 

4. a)What is momentum? b) What is the law of conservation of momentum? 

Answer 1

3. (a)

Kinetic Energy

In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes.

(b)

Potential Energy

In physics, potential energy is the energy possessed by an object because of its position relative to other objects, stresses within itself, its electric charge, or other factors.

(c)

Conservation of energy

In physics, the law of conservation of energy states that the total energy of an isolated system remains constant, it is said to be conserved over time.This law means that energy can neither be created nor destroyed; rather, it can only be transformed from one form to another. For instance, chemical energy is converted to kinetic energy when a stick of dynamite explodes. If one adds up all the forms of energy that were released in the explosion, such as the kinetic energy of the pieces, as well as heat and sound, one will get the exact decrease of chemical energy in the combustion of the dynamite.

4. (a)

Momentum

Momentum is simply the product of mass and velocity of an object.

Momentum is a vector quantity as mass is scaler and velocity is vector quantity.

Rate of change of momentum is also termed as applied force on a object.

(b)

Conservation of momentum

For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision.