P2.2 FORCES

• • A force is defined as:

  A push or a pull that acts on an object due to the interaction with another object
• what 3 things can a force effect?

  change their speed, direction and shape
• what is weight?

  The force exerted on an object due to gravity.
• what is electrostatic force?

  Force between electrically charged objects.
• what is thrust force?

  force causing an object to move.
• what is air resistance or drag?

  friction of the air on a moving object
• what is upthrust force?

  force of a fluid pushing an object upwards.
• what is tension force?

  • force transmitted through a cable or a string when pulled on by forces acting on its opposite ends
• what is a contact force?

  force between objects that are physically touching
• examples of contact forces?

  friction, air resistance, tension, reaction force/normal force
• what is a non-contact force?

  A force which acts at a distance, without any contact between bodies, due to the action of a field
• • Forces working in opposite directions are subtracted from each other
• • Forces working in the same direction are added together
• When an object travels along a circular path, its velocity is always changing
• • This means that an object moving in circular motion travels at a constant speed but has a changing velocity
• Even though the magnitude (speed) doesn’t change, its direction does - so the velocity itself is changing. Because of this, objects in circular motion are always accelerating! 
• examples of non-contact forces?

  gravitational, magnetic, electrostatic