Question

Why is work done by the earth around the sun zero?​

Answer 1

Answer:

BECAUSE as we know

$w = fs \cos( \alpha )$

in the case of earth , earth forms perpendicular to the tangent to the sun.

hence

$w = fs \cos(90) \\ w = 00$

so work done 0.

Answer 2

Answer:

To be clear, read till end pls.

The revolution of Earth around Sun is considered as a circular path (though it is really elliptical).

It is an example of horizontal circular motion.

Work done in a horizontal circular motion is zero.

The reason behind this is that the velocity is along tangential path and force is centripetal (towards centre).

They are actually perpendicular to each other.

W = F. S where F and S are force and displacement vectors respectively.

W = FScos© where © is theta.