forces, movement and changing shape

• What is a force?

  A push or pull from object interaction
• What happens when objects interact?

  Different types of forces occur
• What is gravitational force also known as?

  Weight
• How does mass affect gravitational force?

  Greater mass results in greater gravitational force
• What pulls a football toward the Earth when thrown?

  The gravitational pull of the Earth
• What is a reaction force?

  A push force exerted by a surface
• How does a reaction force act when an object rests on a surface?

  It acts perpendicular to the surface
• What happens when a football rests on grass?

  The grass exerts an upward reaction force

  
• What do frictional forces do?

  They oppose the motion of an object
• When does friction occur?

  When two surfaces move over one another
• What effect does friction have on a box pushed across a carpet?

  It slows down the box's motion
• What is drag force?

  A type of frictional force in fluids
• How does drag force affect an object in a fluid?

  It slows the object's motion
• What happens when a pebble is thrown into water?

  Water molecules slow down the pebble
• What is air resistance?

  A specific type of drag force
• How does air resistance affect a skydiver?

  It opposes their motion and reduces speed

  
• Why does a skydiver open their parachute?

  To increase air resistance and slow down

  
• What is thrust?

  A force produced by an engine
• What does thrust do to an object's motion?

  It speeds up the motion of the object
• What is upthrust?

  An upward push force from a fluid
• What causes a boat to float on water?

  Upthrust exerted by the water
• What happens when a ball is released underwater?

  It shoots upwards due to upthrust
• What is electrostatic force?

  A force between charged objects
• How do like charges interact?

  They repel one another
• How do opposite charges interact?

  They attract one another
• What is magnetic force?

  A force between magnetic poles
• How do like magnetic poles interact?

  They repel one another

  
• How do opposite magnetic poles interact?

  They attract one another
• What is tension?

  A force in a stretched object
• What happens when a pull force is exerted on a rope?

  Tension acts along the length of the rope
• What can forces acting on an object cause?

  Change speed, direction, or shape

  
• How does thrust affect a car?

  It causes the car to speed up
• What is the effect of gravitational pull on a comet?

  It causes the comet to change direction
• What is the definition of a scalar quantity?

  A quantity with magnitude only
• What is an example of a scalar quantity?

  Mass
• What is the definition of a vector quantity?

  A quantity with both magnitude and direction
• What is an example of a vector quantity?

  Weight
• What is distance?

  How far an object has travelled
• How is distance measured?

  Total length of the path taken
• What is displacement?

  Distance between two points including direction