Physics Circle home Student Login

Home›Chapters›Work, Energy and Power PYQs›Work-Energy Theorem›Question 18

JEE Main 2019 (10 Jan, Shift 2) · Work-Energy Theorem

Work-Energy Theorem question from JEE Main 2019 (10 Jan, Shift 2)

Q18JEE Main 2019 · 10 JAN · SHIFT 2Easy

Work-Energy Theorem

A particle which is experiencing a force, given by F⃗=3i^−12j^,\vec{F} = 3\hat{i} - 12\hat{j}, undergoes a displacement of d⃗=4i⃗\vec{d} = 4\vec{i} particle had a kinetic energy of 3 J at the beginning of the displacement, what is its kinetic energy at the end of the displacement?

Show answer and solution

Answer: (d)

  1. W=F⃗⋅d⃗=(3i^−12j^)⋅4i^=12 JW = \vec{F} \cdot \vec{d} = (3\hat{i} - 12\hat{j}) \cdot 4\hat{i} = 12\text{ J}
  2. Kf=Ki+W=3+12=15 JK_f = K_i + W = 3 + 12 = 15\text{ J}
  3. So the answer is (d).
Report a mistake

More questions on Work-Energy Theorem