Question

$\left[a\right]$ Its velocity at the highest point is $\frac{18}{\sqrt{2}}$m/s.
$\left[b\right]$ Its velocity at the highest point is zero.
$\left[c\right]$ If it is thrown at a larger angle to the horizontal, then both its range and maximum height will decrease.
$\left[d\right]$ Range will decrease while maximum height will increase if angle of projection is increased.

A projectile thrown at an angle of $45$ to the horizontal has a range of $32.4m$. Given: $g=10m{s}^{-2}$. Which of the following is correct?

• A. $a$, $b$
• B. $a$, $b$, $d$
• C. $a$, $d$
• D. $b$, $c$, $d$

Answer 1

Answer: (C)

$a$, $d$

$R=\frac{u^{2}sin2\theta }{g}$

$32.4=\frac{u^{2}sin90}{10}$

$\therefore u=18m/s$

horizontal component which will always remain the same is $vcos45=\frac{18}{\sqrt{2}}m/s$

and hence statement $\left[a\right]$ and $\left[d\right]$ are correct