Linear momentum formula
Linear momentum is the product of the mass and velocity of the object. It is a vector quantity because both its direction and velocity change with time. We write linear momentum in kg metres per second.
Importance of linear momentum in physics:
Linear momentum helps us understand previous concepts in physics, one of which is force and quantity of motion. Issac Newton’s Second Law of motion is also based on the relationship between momentum and force. Therefore momentum is very important.
Further, whenever an object is moving, it will definitely possess some momentum. Since most objects move in a linear direction, linear momentum is frequently used to solve physics problems.
The formula for calculating linear momentum:
Here P represents linear momentum, v denotes the velocity of the object and m represents the mass of the object.
If there are ‘n’ numbers of linear momentum, then the total linear momentum will be equal to the sum of all that is P1+P2+P3+P4+ and so on till Pn.
Substituting it with the formula for momentum, we get,
Total momentum = m1v1+ m2v2+ …. Mnvn
Example no. 1: If an object has a mass of 10 kilograms and its velocity is 20 metres per second, what would be the linear momentum of that object?
Solution: m = 10, v= 20 m/s, p=?
We know that formula for calculating linear momentum is p=mv
So, p= 10*20 = 200 kg m/s.
Hence the linear momentum of that object is 200 kilograms metres per second.
Solved example 2: What would be the velocity of an object which has a linear momentum of 300-kilogram metres per second and the mass of the object is 10 kilograms?
Solution: We know that MV is equal to P.
Therefore V is equal to P/M.
Substituting the values, v= 300/10 = 30 m/s.