Scalar and vector

The measures in physics is classified in two division according to their direction.

Scelar measure

Vector measure

Scelar measure is independent with direction on the other hand vector measure is deprndent with direction.

The measure that can not express as its direction is a scelar measure. The measure that required direction to express is vector measure.

F = ma

F = ma

Here, F is denoted for force

m is for mass and a is for acceleration

The force excerted by an object will be the product of mass and its acceleration.

This equation can be derived from Newtons second law of motion.

According to Newtons second law of motion

The rate of change of momentum is proportional to force excerted on it.

Momentum

Momentum is a phenomena that indicates a unique property of any objects or matter is concered with its velocity.

The product of mass and its velocity is called momentum.

Momentum exists when any matter is dynamic. Any static objects momentum will be zero, because in this case the velocity is zero.

Momentum is concerned with force. The higher momentum will be excert higher level of force on some object.

Gravity

Gravity is a phenomena that indicates the force of attraction among the objects. The attraction of earth on a objects is also gravity.

Gravity is one of the fundamental force in universe from out of four fundamental force.

The force of earth on any object depends on a constant value so called gravitational constant and it denoted as g.

The force of earth on the object is depends on the mass of object.

Force is denoted by F
Mass is denoted by m

Hence, F = mg

Acceleration

Acceleration is a phenomena that indicate the rate of change of velocity of the object. The change of velocity of moving object with time is termed as acceleration.

Acceleration may have positive value or negative value. The rate of increasing of velocity is positive acceleration and on the other hand rate of velocity reduction is negative acceleration.