In which situation is no work considered to be done by a force? a. when the angle between the force and displacement is 180° b. when the angle between the force and displacement is 90° c. when the angle between the force and displacement is 45° d. when the angle between the force and displacement is 0°

If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.

If the angle is 45, then there is still some work involved.

The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90. 

The correct answer is option B.

Explanation:

Work done is defined as product of applied force to an object and displacement that is distance covered by an object when force applied.

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be