Question

NO SPAMS PLEASE
In case of a projectile, speed of the particle at the topmost position is half of its initial speed. What is the angle of projection with horizontal plane?

Answer 1

SOLUTIONS.

Why Particle attain highest point during its projectile ?

As we know that when a particle doing projectile motion it have ACCELERATION in y direction which decrease the magnitude of the velocity in y direction after certain period of time the velocity of y direction vanish hence particle no more continue it motion in y direction.

So when velocity of y direction become zero than the particle attain highest point.

so at highest point the velocity is in X direction only

Initial velocity = v

Let the angle of projection be ©

Velocity of X direction = v cos©

ACC to question

v cos©/v = 1/2

cos © = 1/2

© = 60°

#answerwithquality

#BAL

Answer 2

At the topmost position, only horizontal velocity exists. Thus,

$\displaystyle\longrightarrow\sf{u\cos\theta=\dfrac{u}{2}}$

$\displaystyle\longrightarrow\sf{\cos\theta=\dfrac{1}{2}}$

$\displaystyle\longrightarrow\sf{\underline{\underline{\theta=60^o}}}$