Question

what happens to the first equation of motion when a body is at rest​

Answer 1

Explanation:

The equation of motion goes as follows:

v = u + at

S = ut + (1/2)at^2

v^2 = u^2 + 2aS

Where;

v - final velocity of the body

u - initial velocity of the body

a - acceleration of the body

t - time interval

S - displacement of the body

So if the body starts from rest, u=0.

Then the modified set of equations are:

v = at

S = (1/2)at^2

v^2 = 2aS

Answer 2

Explanation:

If a moving body comes to rest, then it's acceleration is negative, as it's velocity becomes zero, therefore the acceleration is also zero

Hope this answer is usefull !