Two blocks of equal mass m are connected by an unstreched spring and placed over a plank moving with an acceleration ′ a ′ as shown in figure. The coefficient of friction between the blocks and platform is μ.

Two bodies of masses 7 kg and 5 kg are connected by a light string passing over a smooth pulley at the edge of the table as shown in the figure. The coefficient of static friction between the surfaces (body and table) is 0.9. Will the mass m_1 = 7 kg on the surface move? If not what value of m_2 should be used so that mass 7 kg begins to slide on the table?

A body slipping on a rough horizontal plane moves wioth a deceleationof 4.0 m/s^ . What is cofficient of kineic friction between the block and the plane?

Two block of equal mass m are connected by an unstretched spring and the sytem is kept at rest on a frictionless horizontal surface. A constant force F is applied on one of the blocks puling it away from the other as shown in figure. a.Find the positon of the centre of mass at time t. b.If the extansion of the spring is x_0 at time t find the displacement of the two blocks at this instant.

A block of mass 2 kg is placed on the floor. The co-efficient of static friction is 0.4. The force of friction between the block and floor is

Find the acceleration of the block of mass M in the situation of figure. The coefficient of friction between the two blocks is mu_1 and that between the bigger block and the ground is mu_2 .