Question

How can I calculate the Newton's second law?

Answer 1

Newton's second law finds that `F=ma`

Explanation:

Newton's second law states that external force `F` is directly proportional to the rate of change of momentum.

If initial velocity of an an object of mass `m` is `u` and after applying uniform force for `t` seconds, its reaches a final velocity becomes `v`,

then its initial momentum is `mxxu=m u` and final momentum is `mxxv=mv` and hence change in momentum is

`mv-m u=m(v-u)`

and as it has taken `t` seconds, rate of change of momentum is `(m(v-u))/t`

But in case of uniform accelaration `a`, we have `v=u+at`

or `(v-u)/t=a` and then rate of change in momentum is `ma`,

hence `Fpropma`

Now we can choose or define a unit of force that corrsponds to unit mass and unit accelaration and then we will have

`F=ma`