Momentum: It is a vector quantity. Its unit is “Kg m/s”.

Equation:  Momentum = mass x velocity.

Linking Force & Momentum: With a resultant force on it , an object will accelerate. Therefore , its velocity will change , and so will its momentum.

Resultant Force: It is the rate of change of momentum.

Equation:  Resultant Force = Change in momentum/ Time.

Impulse Reaction: The quantity of force with time is called impulse reaction.

Equation:  Resultant Force x Time = Change in momentum

 

Conservation of momentum: With the mass and velocity values above the total momentum of the trolleys before and after separation can be found. As momentum is a vector , its direction must be allowed.

Law of Conservation of Momentum:

In a closed system, the sum of the momentum of bodies before collision is equal to the sum of the momentum after the collision.

Equation: m₁u₁ + m₂u₂ = m₁v₁ + m₂v_{2 .}

Types of Collision:

Elastic Collision: When the sum of the kinetic energy in a collision, before and after are equal; the collision is called elastic collision. Eg: Smoker at soft speed.

Inelastic collision: When the sum of the kinetic energy, before and after collision are not equal.

Newton’s Law of Motion:

Newton’s 1^st Law: Everybody continues its state of rest or of uniform motion in a straight line until an external force acts on it.

Newton’s 2^nd Law: To every action there is a reaction of Motion.

Inertia: It is the reluctancy of a body to moves.