Question

What are the three equations of motion ?

Answer 1

Hint: In the physical universe, every object can either be in one of the states. One is called rest which means when an object doesn't change its position with respect to time and another is called motion when an object changes its position with respect to time. Newton discovered three basic equations of motion which gives us the relation between an object’s velocities, acceleration, time and distances covered when it moves.

Complete step by step answer:
 Newton’s first equation of motion is written mathematically as $v = u + at$ where $v,u$ are the final velocity and initial velocity of a body. $a,t$ are the acceleration and time taken by the body. If acceleration is negative which means it's decreasing it's called deceleration.

Newton’s second equation of motion is written mathematically as $S = ut + \dfrac{1}{2}a{t^2}$ where, $a,t$ are the acceleration and time taken by the body.$S,u$ Are the distance covered by the body and initial velocity of the body.Newton’s third equation of motion is written mathematically as ${v^2} - {u^2} = 2aS$ where, $v,u$ are the final velocity and initial velocity of a body.

$S,a$ Are the distance covered by the body and acceleration of the body.Hence, Three equations of motion collectively written as,
First equation: $v = u + at$
Second equation: $S = ut + \dfrac{1}{2}a{t^2}$
Third equation: ${v^2} - {u^2} = 2aS$

Note:It should be remembered that, In physical universe there is nothing like absolute rest or absolute motion, every object in the universe is in motion with respect to any other object while the same object can be at rest with respect to any other object hence, Motion is relative for example two trains moving with same velocity parallel to each other, then each train is at rest with respect to its opposite train while each trains is in motion with respect to the ground, hence motion is relative.