The resultant of two forces acting on an object is maximum when the angle between them is?

A block of wood of mass 5kg is pulled on a platform by a force of 40N as illustrated in the diagram above. If the frictional force, F experienced by the block is 12N, calculate the magnitude of the acceleration of the acceleration of the block

which of the diagrams above shows the position at which a small ball-bearing is in neutral equilibrium?

In the Fig above, MN is a light uniform meter rule pivoted at O, the 80cm mark. A load of mass 3.00kg is suspended on the meter rule at L, the 10cm mark. If the rule is kept in equilibrium by a string RP, fixed at P and attached to the rule at R, the 20cm mark, then the Tension T on the string is?

the fig above shows two connected bodies of masses M1 and M2 in equilibrium under gravity. The tension in the upper string is