Question

at maximum height the kinetic energy of an oblique projectile becomes half of its initial value, determine the angle of projection​

Answer 1

The formula for kinetic energy is E(k)=0.5mv2E(k)=0.5mv2. 
Since projectiles have two velocity components (horizontal and vertical), I’ll answer your question with regards to both.

The vertical velocity of a projectile is zero at its maximum height, so vertically , the projectile will have no kinetic energy. This is because all the energy will have become potential energy at that point.

The horizontal velocity of a projectile is always constant, so you can just plug in the numbers from your question into the formula to determine the kinetic energy.

So basically, at its maximum height, the kinetic energy of a projectile is equal to the amount of kinetic energy calculated with the horizontal velocity, because a projectile still moves horizontally if it’s at rest vertically.

If this confuses you because energy is a scalar quantity, then think of it as you think of time, which is a scalar quantity too.

Hope this Helps

Answer 2

Explanation:

hiii hope it helps ....