Question

B) 60
57. A ball whose kinetic energy Is E, projected at an angle of 60° to the horizontal. The kinetic energy of
the ball at the highest point of its flight will be
A) E
C) E/ V2
B) E14
D) zero
58 Twn stones are projected with same velocity but makes different angles with the horizontal. Their
one is 03 and its maximum height is h, then the

Answer 1

Explanation:

At the highest point of motion ,the vertical component of velocity becomes zero. Only horizontal component of velocity exists and it remains constant through out the motion(if air resistance is neglected).

As kinetic energy is given, it's velocity can be easily derived.

E = (1/2)×M×v^2.

=> V= √(2E/M).

The horizontal component of velocity will be(given angle of projection 60°) vcos60°.

=> V (horizontal) = √(2E/M)×(1/2) = √(E/M×1/2).

=> K.E at heighest point = 1/2×M× v ^2 .( Here v is horizontal velocity).

=> K.E = E/4.