momentum
In fluids usually viscous forces are in action.
Capillary action
Attraction to the Earth is caused by the force of gravity.
coriolis force
friction
Earth's gravity pulling on the Sun.
gravity
action-reaction force
Sun
The mutual force of gravitational attraction between the Earth and Sun.
Basically, it's thought to be because of movements in the plastic mantle below the crust.
Work is the scalar product of the force acting on an object and the displacement caused by that force. In order for work to be done, the object must be moved in the direction of the force.