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Newton’s 3rd Law Of Motion Definition

Newton's 3rd Law of Motion states that for every action, there's an equal and opposite reaction. For example, a rocket moves upwards as gases are expelled downwards.

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Newton’s Laws of Motion

Fun Facts

  • A ball bounces back with an equal force when thrown down.
  • When water squirts one way, the hose handle moves the opposite way.
  • A balloon moves in the opposite direction of air pushing out.

Why Do We Need To Know About Newton's 3rd Law Of Motion

Newton’s 3rd law of motion tells us that every action has an equal and opposite reaction, which helps us understand how things move together. This idea is important for engineers who design things like rockets and water jets. For example, rockets move up because they push gases out downwards, and water jets, like the ones used in flyboards, work by pushing water out to lift the rider up.

This law is also used to make cars safer. Engineers use it to design airbags and parts of the car that squish to absorb shock in a crash, protecting the people inside. These examples show how Newton’s 3rd law is key to making safe and effective transportation.

Frequently Asked Questions

Newton’s first law of motion states that an object's motion remains the same unless a force acts upon it. What would be an example of this law in action?
If a ball is still, it will remain still until a force, such as a kick, makes it move.
Newton’s second law of motion states that larger things need more force to move them than lighter things. What would be an example of this law in action?
One example is pushing a car or pushing a shopping cart. You would need much more force to push a car the same distance as a shopping cart.
Why do people need to know about Newton’s Laws of Motion?
Newton’s laws of motion are helpful when making predictions of motion. This might be important if you were trying to step off a boat onto a dock. If you push off the boat, it will move away from the dock a little, which would be important to know if you don’t want to end up in the water.
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