Derive the formula for Range of a projectile $(R)$. Derive the formula for maximum projectile.
Range is defined as the horizontal distance travelled by a projectile from its initial position $y=0$ ) to the final position (where it passes $y=0$ during its fall) is called the Range of the projectile.
or it is the distance travelled from its initial position $(x=0, y=0)$ to final position $(x=\mathrm{R}, y=0)$ is called 'R'.
At any instant of time keeping $x=\mathrm{R}$ and $\mathrm{t}=\mathrm{t}_{\mathrm{F}}$ then $x=\left(v_{0} \cos \theta_{0}\right) t$
$\therefore \mathrm{R}=\left(v_{\mathrm{o}} \cos \theta_{\mathrm{o}}\right) t_{\mathrm{F}}$
$\therefore \mathrm{R}=\left(v_{\mathrm{o}} \cos \theta_{\mathrm{o}}\right)\left(\frac{2 v_{o} \sin \theta_{o}}{g}\right)\left[\because t_{\mathrm{F}}=\frac{2 v_{o} \sin \theta_{o}}{g}\right]$
$\therefore \mathrm{R}=\frac{2 v_{o}^{2} \sin \theta_{o} \cos \theta_{o}}{g}$
$\therefore \mathrm{R}=\frac{v_{o}^{2}\left(\sin \theta_{o} \cos \theta_{o}\right)}{g}$
$\therefore \mathrm{R}=\frac{v_{o}^{2} \sin 2 \theta_{o}}{g}$
$\mathrm{R}_{\max }$ is given by $\frac{v_{o}^{2}}{g}$
When $\sin 2 \theta_{0}=1$
For $\mathrm{R}_{\max } \quad \sin 2 \theta_{\mathrm{o}}=1 .$
$\therefore 2 \theta_{\mathrm{o}}=90^{\circ}$
$\therefore \theta_{\mathrm{o}}=45^{\circ}$
If the object is at an angle $\theta_{o}=45^{\circ}$, then its range is maximum. The value of $R_{\max }$ depends upon its initial velocity.
A particle is projected in air at some angle to the horizontal, moves along parabola as shown in figure where $x$ and $y$ indicate horizontal and vertical directions respectively. Shown in the diagram, direction of velocity and acceleration at points $A, \,B$ and $C$.
A shell fired from the base of a mountain just clears it. If $\alpha$ is the angle of projection then the angular elevation of the summit $\beta$ is
Two seconds after projection a projectile is travelling in a direction inclined at $30^o$ to horizontal, after one more second it is travelling horizontally. What is the magnitude and direction of its velocity at initial point
Trajectory of particle in a projectile motion is given as $y=x-\frac{x^2}{80}$. Here, $x$ and $y$ are in metre. For this projectile motion match the following with $g=10\,m / s ^2$.
$Column-I$ | $Column-II$ |
$(A)$ Angle of projection | $(p)$ $20\,m$ |
$(B)$ Angle of velocity with horizontal after $4\,s$ | $(q)$ $80\,m$ |
$(C)$ Maximum height | $(r)$ $45^{\circ}$ |
$(D)$ Horizontal range | $(s)$ $\tan ^{-1}\left(\frac{1}{2}\right)$ |
Two balls are projected with the same velocity but with different angles with the horizontal. Their ranges are equal. If the angle of projection of one is $30^{\circ}$ and its maximum height is $h$, then the maximum height of other will be