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Home > Physics > Revision videos > Newton's first law


Newton's first law

Newton's first law video

Newton’s First Law is about balanced and unbalanced forces. This video demonstrates how these forces affect the motion of an object.

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Key points

  • Forces are said to be balanced if there are equal forces acting in opposite directions.
  • Balanced forces are equivalent to no force at all.
  • If there are no forces on an object or the forces are balanced, the object's speed does not change - it will be at rest or moving at a constant speed.
  • If the forces on an object are unbalanced, the object will either accelerate or decelerate.
  • Friction and air resistance are forces which oppose motion.

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