Which of the following statements is not correct? Statement 1 (S1): Friction is a force that attracts objects towards each other. Statement 2 (S2): Friction arises due to irregularities in the surfaces of objects in contact, which resist motion by creating interlocking.

One block of 2.0 kg mass is placed on top of another block of 3.0 kg mass. The coefficient of static friction between the two blocks is 0.2. The bottom block is pulled with a horizontal force F such that both blocks move together without slipping. Taking acceleration due to gravity as 10 m/s2, the maximum possible value of the frictional force between the two blocks is:

A body weighing 100 kN is placed on a rough horizontal plane. Determine the coefficient of static friction if a horizontal force of 30 kN just causes the body to slide over the plane.