# forces

• forces
• a force is a push or pull motion on any object
• they are all either non contact or contact
• when 2 objects interact there is always a force produced on both objects
• non-contact
• these are forces in which the objects do not need to be touching for forces to act
• e.g: magnetic forces, gravity,
• scalar quantities
• e.g.: distance, time, mass, temperature, speed
• can have magnitude or size but do not have any direction
• vector quantities
• e.g.: force, velocity, acceleration, displacement, momentum
• most physical quantities are vector
• vectors are shown in free body diagrams with the length of the arrows representing the size of the quantities
• free body diagrams
• if all in the free body diagrams are equal in length the object is either moving at a constant speed or is not moving
• the upwards facing arrow represents upthrust ; the south facing arrow represents weight ; the east facing arrow represents drag ; the west facing arrow represents thrust
• vector quantites are forces which can have magnitude or size and always have direction
• contact forces
• forces where the 2 objects need to be touching for the force to act
• e.g.: friction, air resistance, tension