The coefficient of static friction, $$\mu $$_s, between block A of mass 2 kg and the table as shown in the figure is 0.2. What would be the maximum mass value of block B so that the two blocks do not move? The string and the pulley are assumed to be smooth and massless. (g = 10 m/s²)

A man weight 80 kg. He stands on a weighting scale in a lift which is moving upwards with a uniform acceleration of 5 m/s². What would be the reading on the scale ? (g = 10 m/s²)

A monkey of mass 20 kg is holding a vertical rope. The rope will not break when a mass of 25 kg is suspended from it but will break if the mass exceeds 25 kg. What is the maximum acceleration with which the monkey can climb up along the rope ? (g = 10 m/s²)

An object of mass 3 kg is at rest. Now a force of $$\overrightarrow F $$ = 6t² $$\widehat i$$ + 4t $$\widehat j$$ is applied on the object then velocity of object at t = 3 sec. is