Question

As shown in the figure a projectile is fired with a horizontal velocity of $330\text{m/s}$ from the top of a cliff $80\text{m}$ high. How far from the foot of the cliff will it strike?

• A. $660\text{m}$
• B. $1320\text{m}$
• C. $330\text{m}$
• D. $2640\text{m}$

Answer 1

The correct option is B $1320\text{m}$

Time taken by the projectile to reach ground
$T=\sqrt{\frac{2H}{g}}=\sqrt{\frac{2\times 80}{10}}$
$T=4\text{s}$
Horizontal distance covered by the projectile
$x=u_x\times T$ where $u_x$ is the horizontal velocity of projection.
$x=330\times 4=1320\text{m}$