Newton's First Law Physics Example 3

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Example 3

easy
A car travels at a constant velocity of 20 m/s20 \text{ m/s} on a straight road. What is the net force acting on the car?

Solution

  1. 1
    Constant velocity means zero acceleration: a=0a = 0.
  2. 2
    By Newton's first law (or second law): Fnet=ma=m×0=0 NF_{\text{net}} = ma = m \times 0 = 0 \text{ N}

Answer

Fnet=0 NF_{\text{net}} = 0 \text{ N}
An object moving at constant velocity has no acceleration, which means the net force on it is zero. The driving force exactly balances friction and air resistance.

About Newton's First Law

An object at rest stays at rest, and an object in motion continues moving at constant velocity in a straight line, unless acted upon by.

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More Newton's First Law Examples

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Example 2 medium

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Example 4 medium

A bus travels at [formula] and brakes suddenly. A backpack on the floor slides forward. According to

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