5.6.4 Newton's Laws of Motion

• What is a force defined as in physics?

  A push or pull
• Motion refers to an object's change in position
• Contact forces require physical touch between objects.
• What is an example of a non-contact force?

  Gravity
• Newton's First Law of Motion states that an object remains at rest or in uniform motion unless acted upon by a net force
• What is the principle of inertia in Newton's First Law of Motion?

  Resistance to changes in motion
• Newton's First Law of Motion is also known as the law of inertia
• What is the SI unit for force?

  Newton
• A magnetic force is an example of a non-contact force.
• What are non-contact forces?

  Forces without physical contact
• Gravity is a non-contact force that pulls objects towards each other
• Newton's First Law of Motion is also known as the law of inertia.
• What happens to your body when you brake suddenly in a car due to inertia?

  Continues forward until restrained
• Newton's First Law states that an object remains at rest unless acted upon by a net force
• Match the concept with its description:

  Force ↔️ Measured in Newtons

  Mass ↔️ Measured in kilograms

  Acceleration ↔️ Measured in m/s²
• What is the acceleration of a 50 kg shopping cart if a 100 N force is applied?

  2 m/s²
• Newton's Third Law states that for every action, there is an equal and opposite reaction.
• What is the direction of the reaction force in Newton's Third Law?

  Opposite to the action
• Newton's Third Law states that forces between interacting objects are equal in magnitude and opposite in direction
• The action force is the initial force applied by one object.
• What is the reaction force when you push against a wall?

  The wall pushing back
• Steps to explain Newton's Third Law with a rocket example:

  1️⃣ Rocket expels gas downwards

  2️⃣ Gas exerts an upward force on the rocket

  3️⃣ Rocket accelerates upwards
• What is the reaction force when a rocket expels gas downwards?

  Gas pushing the rocket upwards