JEE Main Physics question
A force of 19.6 N when applied parallel to the surface just moves a body of mass 10 kg kept on a horizontal surface. If a 5 kg mass is kept on the first mass, the force applied parallel to the surface to just move the combined body is
Answer: (A)
Solution
From the first case, μ = F/(mg) = 19.6/(10×9.8) = 0.2. With the combined mass (15 kg), force required = μ×15×9.8 = 0.2×147 = 29.4 N.