A ball is projected with kinetic energy E, at an angle of 60∘ to the horizontal. The kinetic energy of this ball at the highest point of its flight will become :
(A)Zero
(B)2E
(C)4E✓ Correct
(D)E
Answer: (C)
Solution
Initial kinetic energy E=21mu2. At the highest point of projectile motion, only the horizontal component of velocity remains: v=ucos60∘=2u. The kinetic energy at the highest point is KE=21m(2u)2=21m4u2=41(21mu2)=4E.
JEE Main · 2022 · 29 Jul 2022 · Shift 1 · Single correct option