Question

state the newtons second law is real law

Answer 1

Dear Student,

Newton's 2nd law states that "The rate of change of momentum is directly proportional to the applied force".
Or in other words
Newton's second law states that the force applied to a body produces a proportional acceleration; the relationship between the two is: -

F=ma

where F is the force applied, m is the mass of the body, and a is the body's acceleration.

Even the first law can be proved by this one: -
if force applied is zero, then
ma=0

Because mass cannot be zero for a body, so acceleration must be zero.

Thus, a body remains in a state of rest until force acts on it (f=0; a=0),
and it remains in a state of unaccelerated motion until force acts on it (f=0; a=0).