Question

Question Number: 25
section
Questid
A projectile is projected with kinetic energy of 800 J. If it has the maximum possible horizontal range, then its kinetic
energy at the highest
point will be
16
(A) 800J
(B) 400J
20
(C) 200J
24
(D) 100J​

Answer 1

Answer:

400j

Explanation:

when angle is 45° the kinetic energy will be highest at K/2j, in this case it is 800/2 that is 400.

I hope it helps :-)

Answer 2

Answer:

if it has the maximum possible horizontal range, then its kinetic energy at the highest point will be 400J

Explanation:

At the maximum possible horizontal range,

θ=45°

∴ $H=u^{2} /4g$

The potential energy at that point can be given by,

$mgh=1/4mu^{2}$

The potential energy at the maximum possible horizontal energy is half of the kinetic energy at the ground.

$KE=1/2mu^{2}$

Thus, KE at top = KE-KE/2 = 800-400 = 400

Thus, If it has the maximum possible horizontal range, then its kinetic energy at the highest point will be 400J