ExamBro
ExamBro
JEE Mains · Physics · STD 11 - 3.2 motion in plane

A ball of mass 100 g is projected with velocity \(20 \mathrm{~m} / \mathrm{s}\) at \(60^{\circ}\) with horizontal. The decrease in kinetic energy of the ball during the motion from point of projection to highest point is

  1. A 5 J
  2. B 15 J
  3. C 20 J
  4. D zero
Verified Solution

Answer & Solution

Correct Answer

(B) 15 J

Step-by-step Solution

Detailed explanation

\begin{aligned} & \mathrm{k}_{\mathrm{i}}=\frac{1}{2} \mathrm{mv}^2 \\ & \mathrm{k}_{\mathrm{f}}=\frac{1}{2} \mathrm{~m}\left(\mathrm{v} \cos 60^{\circ}\right)^2=\frac{1}{8} m v^2 \\ & \Delta \mathrm{k}=\mathrm{k}_{\mathrm{i}}-\mathrm{k}_{\mathrm{f}}=\frac{3}{8}…

Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app