In which of the following cases no work is done by the force?

In which of the following case of work done by a force will be maximum : when the angle between the direction of force and direction of motion is 0^(@) or 90^(@) ?

Figure shows four situations in which a force is applied to a block. In all four cases, the force has the same magnitude, and the displacement of the block is to the right and of the same magnitude. Which of the following cases work done by the applied force on the block zero?

Figure shows four situations in which a force is applied to a block. In all four cases, the force has the same magnitude, and the displacement of the block is to the right and of the same magnitude. Which of the following cases work done by the applied force on the block zero?

In which of the following cases is the work done positive or zero or negative ? Work done by force of gravity on a ball thrown up vertically up into the sky.

In which of the following cases is the work done positive or zero or negative ? Work done by the force of gravity on suitcase as the suitcase falls from porter's head.

In which of the following, the work done by the mentioned force is negative ? The work done by

In which of the following cases is the work done positive or zero or negative ? Work done by the porter on a suitcase in lifting it from the platform on to his head.

In which of the following cases can the work done increase the potential energy?