Normal Force Physics Example 2

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Example 2

medium
A 5 kg5 \text{ kg} block rests on a ramp inclined at 30°30° to the horizontal. What is the normal force on the block? Use g=9.8 m/s2g = 9.8 \text{ m/s}^2.

Solution

  1. 1
    On an incline, the normal force balances only the component of weight perpendicular to the surface.
  2. 2
    Weight component perpendicular to the ramp: W⊥=mgcos⁡θ=5×9.8×cos⁡30°W_{\perp} = mg\cos\theta = 5 \times 9.8 \times \cos 30°
  3. 3
    N=W⊥=49×0.866=42.4 NN = W_{\perp} = 49 \times 0.866 = 42.4 \text{ N}

Answer

N≈42.4 NN \approx 42.4 \text{ N}
On an inclined surface, the normal force is less than the weight because only the perpendicular component of gravity is balanced. The steeper the ramp, the smaller the normal force.

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 1 easy

A [formula] box rests on a horizontal floor. What is the normal force acting on the box? Use [formul

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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