KCET 2026 Physics Solved Paper

Concept:A constant force on a frictionless surface produces uniform acceleration, which changes the kinetic energy of the body from zero to a final value.Explanation:Since the table is frictionless, the entire applied force is used to accelerate the body without any loss of energy.Given: $F = 5\ \mathrm{N}$, $m = 5\ \mathrm{kg}$, initial velocity $u = 0\ \mathrm{m\,s^{-1}}$, and time $t = 10\ \mathrm{s}$.Using Newton's second law, $F = ma$, we get:$$a = \frac{F}{m} = \frac{5}{5} = 1\ \mathrm{m\,s^{-2}}$$Now, using the first equation of motion, $v = u + at$:$$v = 0 + 1 \times 10 = 10\ \mathrm{m\,s^{-1}}$$The body starts from rest, so its initial kinetic energy is $K_i = 0\ \mathrm{J}$.The final kinetic energy is given by:$$K_f = \frac{1}{2}mv^2 = \frac{1}{2} \times 5 \times (10)^2 = \frac{1}{2} \times 5 \times 100 = 250\ \mathrm{J}$$Therefore, the change in kinetic energy is:$$\Delta K = K_f - K_i = 250 - 0 = 250\ \mathrm{J}$$Answer:$250\ \mathrm{J}$, which is Option D.