When can work done by a force be positive negative and zero?

Hence, work is positive. Zero work – the work done is said to be zero when force and displacement are perpendicular to each other. Negative work done – The work done is said to be negative when force and displacement are in opposite directions.

How do you determine if the work by a force is positive negative or zero?

Work done by a force F on an object, the displacement of which is . If F and are in the same direction, work done by F is positive. If F and are in the opposite direction, work done by F is negative.

Is work done by a force positive or negative?

Work can be either positive or negative: if the force has a component in the same direction as the displacement of the object, the force is doing positive work. If the force has a component in the direction opposite to the displacement, the force does negative work.

When work done is positive and negative?

When the direction of motion of the body and the force acting in the same direction, work done is positive. When the direction of motion of the body and the force acting on the body is opposite, work done is negative.

When we can say that work done by a force is negative?

Negative work – When the force is acting opposite to the direction of the displacement, the work done by the force is taken as negative.

When work done by a force is positive?

Positive work is done by a force when the displacement of the body is in the direction of the force applied whereas negative work is done by the force when the direction of the displacement of the body is opposite to the direction of the force.

When work done is said to be zero?

Zero work is done when the displacement of a body is zero or perpendicular (θ=900,cosθ=0) to the direction of force applied, then work done is zero. For example, if a person tries to push a wall, he is applying force yet the wall does not move, so the displacement of the wall is zero, and hence work done is zero.

What are the two conditions when the work done is zero?

Two conditions when the work done is zero are: (i) When there is no displacement (S=0) and, (ii) When the displacement is normal to the direction of the force (θ=90o).

What is the condition of negative work done?

If the displacement of the body is in the direction opposite to the force, then work done is negative. For example: When a body moves on a surface, the force of friction between the body and the surface is in direction opposite to the motion of the body and so the work done by the force of friction is negative.