Question

Two blocks A and B of masses 6 kg and 3kg rest on a smooth horizontal surface as shown in the figure. If coefficient of friction between A and B is 0.4, the maximum horizontal force which can make them without separation is 1) 72 N 2) 40 N 3) 36 N 4) 20 N

Answer 1

72 N is the correct answer

Answer 2

Answer:

Explanation:

Maximum force on 3Kg

 = Umg = 0.4 x 30 = 12N

Acceleration of 3Kg = F/m = 12/3 = 4m/s^2

Horizontal force = (m1 +m2)a = 9 x 4 =36N