Question

How to find final speed?

Answer 1

Hint: There are different ways to find the final speed, so to determine a single formula for getting final speed is not possible. So, to write the solution for this question, it's better to explain the most appropriate formulas that could be used to get the final speed. The equation of motion is one such topic that can be used to find final speed and is used widely in physics.

Complete answer:
Final Velocity is defined as the Velocity attained by a body after completing or reaching a certain distance or a given or certain time interval.
In case of uniform acceleration, there are three equations of motion which are also known as the laws of constant acceleration. So, these equations can only be applied when acceleration is constant, and motion is a straight line. The three equations are,
$\begin{align}
  & 1)\,\,\,v=u+at \\
 & 2)\,\,{{v}^{2}}={{u}^{2}}+2as \\
 & 3)\,\,s=ut+\dfrac{1}{2}a{{t}^{2}} \\
\end{align}$
where,
$\begin{align}
  & s=\text{Displacement} \\
 & u=\text{Initial Speed} \\
 & v=\text{Final Speed} \\
 & a=\text{Acceleration} \\
 & t=\text{Time of Motion} \\
\end{align}$
Now, to find the final speed we can use any of the above 3 equations depending on the details given in the question. Combination of the above equation can also be used to find the final speed.
Therefore, there are different ways of finding the final speed, which depends on the information given in the question.

Note:
Usually when it is asked to find the final speed, then there are additional details also given in the question, which will help to determine the formula that should be used to find the final speed. There are different types of formulas that could be used to find the final speed, but all these formulas depend on the variable used in it, so to use the most appropriate formula, it is necessary to understand what all values are given in the question.