Aforce does work on an object if a component of the force: a. is perpendicular to the displacement of the object b. is parallel to the displacement of the objectc. is crossing the line of axis d. both a and b are correct

To obtain the value of work done on object, a component of the force is parallel to the displacement of the object. Hence, option (b) is correct.

The force applied any object to displace it from a given point to another point is known as work done on the object. The mathematical expression for the work done on an object is given as,

Here,

W is the work done

f is the magnitude of applied force

d is the displacement of the object.

 is the angle between the applied force and displacement.

To obtain a work, the value of  must be 1. Which is possible when .

However, this shows that to have some work done on object, the displacement of the object should be in the same direction as the applied force or we can say, that displacement needs to be parallel to the applied force.

Thus, we can conclude that to obtain the value of work done on object, a component of the force is parallel to the displacement of the object. Hence, option (b) is correct.

Learn more about the work done by applied force here:

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As we know that total work done by a force is given by

so it is product of force and displacement along same direction

as we can write it as

so it must be the product of force and displacement in same directions so correct answer must be

b. is parallel to the displacement of the object