The support force that acts against gravity is called...

• A. Normal Force
• B. Friction
• C. Tension Force
• D. Gravitational Force

Answer: (A)

The normal force is the support force exerted by a surface on an object in contact, directed perpendicular to that surface and opposite to the direction the object would move into the surface. It acts to prevent penetration and to support the weight of the object. On a flat horizontal surface, the normal force balances the weight, so the net vertical force is zero and the object can stay at rest or move with constant velocity. Other forces at play would be friction, which acts parallel to the surface, and tension, which comes from ropes or cords; gravitational force is the downward pull of gravity. So the force that provides the upward support against gravity is the normal force.