JEE Main · 2025 · 23 Jan 2025 · Shift 2 · Kinematics

A ball having kinetic energy KE, is projected at an angle of

6 0^{\circ}

from the horizontal. What will be the kinetic energy of ball at the highest point of its flight?

(A) $\frac{( KE )}{8}$
(B) $\frac{( KE )}{4}$ ✓ Correct
(C) $\frac{( KE )}{16}$
(D) $\frac{( KE )}{2}$

Answer: (B)

Solution

Let the ball be launched with speed

u

6 0^{\circ}

to the horizontal, so

K E = \frac{1}{2} m u^{2}

At the highest point the vertical component of velocity vanishes, leaving only the horizontal component

u cos 6 0^{\circ} = u /2

K E^{'} = \frac{1}{2} m (\frac{u}{2})^{2} = \frac{1}{4} (\frac{1}{2} m u^{2}) = \frac{K E}{4}

The kinetic energy at the highest point of the flight is

\frac{K E}{4}

JEE Main · 2025 · 23 Jan 2025 · Shift 2 · Single correct option

Practise more: all JEE Main PYQs on Kinematics →

More JEE Main questions on Kinematics

A projectile is thrown upward at an angle $6 0^{\circ}$ with the horizontal. The speed of the projectile is 20 m/s when its direction of motion is $4 5^{\circ}$ with the horizontal. The initial speed of the projectile is ______ m/s.
JEE Main 2026View solution →
A river of width 200 m is flowing from west to east with a speed of $18 km / h$ . A boat, moving with speed of $36 km / h$ in still water, is made to travel one-round trip (bank to bank of the river). Minimum time taken by the boat for thi …
JEE Main 2026View solution →
An object is projected with kinetic energy K from a point A at an angle $6 0^{\circ}$ with the horizontal. The ratio of the difference in kinetic energies points B and C to that at point A (see figure), in the absence of air friction is :
JEE Main 2026View solution →
A block is sliding down on an inclined plane of slope $θ$ and at an instant $t = 0$ this block is given an upward momentum so that it starts moving up on the inclined surface with velocity $u$ . The distance $(S)$ travelled by the block before its velocity become zero, …
JEE Main 2026View solution →
A paratrooper jumps from an aeroplane and opens a parachute after 2 s of free fall and starts deaccelerating with $3 m / s^{2}$ . At 10 m height from ground, while descending with the help of parachute, the speed of paratrooper is …
JEE Main 2026View solution →
A bead $P$ sliding on a frictionless semi-circular string $(A C B)$ and it is at point $S$ at $t = 0$ and at this instant the horizontal component of its velocity is $v$ . Another bead $Q$ of the same mass as $P$ is ejected from point $A$ at $t = 0$ …
JEE Main 2026View solution →