Question

Why the work in case of Vertical is W(f)=F*d
because : cos (90) = 0 ?
or because : cos (0) = 1 ?
i dont understand ...

Answer 1

work is a scaler

Answer 2

You just take the coordinate system to be so. You have a force of weight pointing downwards (towards the centre of the Earth) and the Work (potential energy) is mgh, where mg=F, g=a, h=d. Although you should not confuse work with potential energy, because with the case of work we are talking about a distance that is being covered, and the potential energy is supposable work that can be done. When you have a body that is projected at some angle alpha over the horizon, the vertical COMPONENT is u*sin(alpha), where u is the initial speed.

Answer 3

ok , what about the work (a-b) without potential energy

Answer 4

I don't understand your question?

Answer 5

You talk about the work of gravity
what about other works

Answer 6

If they are parallel to the y-axis you add or substract them from the force of gravity. If they are not parallel with the y-axis you add or substract a*sin(alpha) (the component)

Answer 7

sorry, a*sin(alpha)*m, where m is mass and a acceleration

Answer 8

It is difficult to understand what you are talking about. Can you draw a picture, please?

Answer 9

Are you reffering to me?

Answer 10

No, I meant AntarAzri :)

Answer 11

Okay :)