Derive the equations of uniformly accelerated motion by the graphical method.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) Let the velocity of the particle at $t=0$ be $v_{0}$ and at time $t$ be $v$.
$1$. First Equation of Motion $(v = v_{0} + at)$:
The acceleration $a$ is the slope of the velocity-time graph line $AB$.
$a = \text{slope} = \frac{v - v_{0}}{t - 0} = \frac{v - v_{0}}{t}$
$\therefore v = v_{0} + at$.
$2$. Second Equation of Motion $(x = v_{0}t + \frac{1}{2}at^{2})$:
The displacement $x$ is the area under the $v-t$ graph (trapezium $OABD$).
$x = \text{Area of rectangle } OACD + \text{Area of } \Delta ACB$
$x = (v_{0} \times t) + \frac{1}{2} \times (t) \times (v - v_{0})$
Since $(v - v_{0}) = at$,we get:
$x = v_{0}t + \frac{1}{2}at^{2}$.
$3$. Third Equation of Motion $(v^{2} - v_{0}^{2} = 2ax)$:
The displacement $x$ is the area of the trapezium $OABD$.
$x = \frac{1}{2} \times (\text{sum of parallel sides}) \times \text{height}$
$x = \frac{1}{2} (v_{0} + v) \times t$
Since $t = \frac{v - v_{0}}{a}$,we substitute $t$:
$x = \frac{1}{2} (v + v_{0}) \times \frac{(v - v_{0})}{a}$
$2ax = v^{2} - v_{0}^{2}$
$\therefore v^{2} = v_{0}^{2} + 2ax$.

Explore More

Similar Questions

$A$ particle is projected with velocity $v_0$ along the $x$-axis. The deceleration of the particle is proportional to the square of the distance from the origin,i.e.,$a = -\alpha x^2$. The distance at which the particle stops is:

Difficult
View Solution

The velocity of a bullet is reduced from $200\; m/s$ to $100\; m/s$ while travelling through a wooden block of thickness $10\; cm$. The retardation,assuming it to be uniform,will be ........... $\times 10^4\; m/s^2$.

Difficult
View Solution

$A$ particle starts moving from rest in a straight line with constant acceleration. After time $t_0$,the acceleration changes its sign (becomes exactly opposite to the initial direction),while remaining the same in magnitude. Determine the time from the beginning of the motion at which the particle returns to its initial position.

Difficult
View Solution

$A$ car accelerates from rest at a constant rate $\alpha$ for some time,after which it decelerates at a constant rate $\beta$ and comes to rest. If the total time elapsed is $t$,then the maximum velocity acquired by the car is

$A$ vehicle starts from rest and accelerates along a straight path at $2 \,m/s^2$. At the starting point of the vehicle, there is a stationary electric siren. How far has the vehicle nearly gone when the driver hears the siren at $94 \%$ of its original frequency when the vehicle was at rest (in $\,m$)? (Speed of sound $= 330 \,m/s$)

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo