Question

(1)Write joules law of heating
(2)explain "conservation of momentum"

Answer 1

1. The heat which is produced due to the flow of current within an electric wire, is expressed in unit of Joules. ... The heat generated due to the flow of current is proportional to the time of current flowing, when the electrical resistance and the amount of current is constant.

The law of momentum conservation can be stated as follows. 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.

Answer 2

1) ==>> According to joules law of heating the current*I* flows through a resistor *R* for time *T* then some heat is produces in joules which is directly proportional to the square of current flowing through it and to its resistance and the time for which the current flows.

Which is H = I^2 × R × T.

2) According to the conservation of momentum the total momentum before collision is = to the total momentum after collision for bodies.

That is if a body of mass M1 with velocity V1 and another body of mass M2 with velocity V2.

Then the sum of the momentum of both body before collision is equal to the sum of momentum after collision.