Ignite coaching classes

https://youtu.be/4hbkSYGPiAU

4-Resistances-in-series-chapter-12-electricity-ncert-science-class-10 This video explains resistancers in series with experimwent.

Total Work done by kuli in displacement of an object?

Few books have incorrect interpretation that work does equals to zero.
But basically kuli has done 3 works in different directions.
1. picking up the object,
2. Holding object and moving forward.
3. Relieving object at the place.

Here first and third work is in opposite direction so it will get cancelled by each other.

Now we have left with the work done by 2nd.

Here few books explain while holding we apply the force perpendicular to the ground, that's where it gets wrong since force is a reaction of the kuli from the ground that has a forward component
therefore force applied on the object will have a direction in mid of horizon and perpendicular.

Therefore total work done is not zero when displacement is not zero.

2nd explanation I found somewhere that gravity potential for earth like system everywhere is same. Therefore work done is 0.

This is incorrect in the sense, that gravity potential is same for surfaces which are purely spherical, but earth's shape is an oval. So it is incorrect explanation as well.