Question

A projectile is projected with speed $49\,ms^{-1}$ at an angle of $30^{\circ}$ with horizontal. The time taken by the projectile to reach the highest point is

• A. $2\,s$
• B. $2.5\,s$
• C. $3.5\,s$
• D. $4.5\,s$

Answer 1

Answer: (B)

$2.5\,s$

Answer 2

Here, Velocity of projection, $u=49\, m \, s^{-1}$ Angle of projection, $\theta=30^{\circ}$ Time taken by the projectile to reach the highest point is $t=\frac{u\,sin\,\theta}{g}$ $=\frac{\left(49\,m\,s^{-1}\right)\left(sin\,30^{\circ}\right)}{9.8 \, m \,s^{-2}}$ $=2.5 \, s$