Forces

A push or pull on an object that can cause objects to move, stop moving, change speed, or change direction

• speed

• force

• gravity

• friction

What are the three characteristics of all forces? (Pick 3 answers.)

• All forces have direction.

• All forces are balanced.

• All forces have magnitude and strength.

• All forces are measured in Newtons (N).

• All forces are non-contact.

Sort the forces into contact and non-contact.

Groups:

(a) Contact Forces

,

(b) Non-contact Forces

• Buoyancy

• Friction

• Tension

• Normal force

• Spring force

• Magnetic force

• Electric force

• Gravitational force

• Applied force

The force that results when two objects physically touch each other

• non-contact force

• balanced force

• contact force

• unbalanced force

Match the following words to their definitions.

• Friction

• when two objects pull on a rope, string, wire, or cable in opposite directions

• Applied force

• a force created by a stretched or compressed spring

• Tension

• a force that opposes motion and works in the opposite direction of a moving object

• Spring force

• a force applied by a person or object onto another object

• Normal force

• a force exerted by a surface on an object resting on that surface

A fluid pushes upward on an immersed object

• non-contact force

• friction

• buoyancy

• gravity

An applied force can be a push or a pull. A push is applying a force that causes an object to move​ (a)   the object or person that is pushing. A pull is applying a force that causes the object to move​ (b)   the object or person that is pulling.

• away from
• towards

The force of friction exerted by a surface depends on the smoothness of the surface. A​ (a)   surface has less friction than a​ (b)   surface. The surface of the objects can be coated with​​ (c)   to reduce the friction.

• smooth
• rough
• liquid

The force that results when two objects do not physically touch each other

• non-contact force

• balanced force

• contact force

• unbalanced force

Match the following words to their definitions.

• Magnetic force

• a force created by magnets

• Electric force

• a force of attraction between two objects

• Gravitational force

• an invisible force created by electrically charged particles