Normal Force Physics Example 1

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Example 1

easy
A 8 kg8 \text{ kg} box rests on a horizontal floor. What is the normal force acting on the box? Use g=9.8 m/s2g = 9.8 \text{ m/s}^2.

Solution

  1. 1
    The box is in equilibrium on a horizontal surface, so the net vertical force is zero.
  2. 2
    The normal force must balance the weight: N=mg=8×9.8=78.4 NN = mg = 8 \times 9.8 = 78.4 \text{ N}
  3. 3
    The normal force acts perpendicular (normal) to the surface, directed upward.

Answer

N=78.4 N upwardN = 78.4 \text{ N upward}
The normal force is the contact force exerted by a surface perpendicular to that surface. On a flat horizontal surface with no other vertical forces, the normal force equals the object's weight.

About Normal Force

The perpendicular contact force that a surface exerts on an object pressing against it, directed away from the surface.

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More Normal Force Examples

Example 2 medium

A [formula] block rests on a ramp inclined at [formula] to the horizontal. What is the normal force

Example 3 medium

A [formula] box on a horizontal floor has a [formula] downward push applied to it. What is the norma

Example 4 hard

A person ([formula]) stands in an elevator accelerating upward at [formula]. What normal force does

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