Revision 2 as of 9:04AM, Sep 29, 2011

Which force?

Friction, air resistance, tension, spring force, normal force, etc. are all due to

  1. Gravitational force
  2. Electromagnetic force
  3. Strong force
  4. Weak force

The force is everywhere

When two objects exchange forces, they can do so without having to contact each other.

  1. Yes
  2. No