What is net force?

•All the forces acting on an object

• If the forces acting on an object are going in the same direction, you would _________ them together to get the net force.

•ADD

• If the forces are acting on an object are going in opposite direction to each other, you would _________ them together to get the net force.

•Subtract

•What is inertia?

•The tendency of an object to resist a change in its motion

•The greater the mass of an object will ______ its inertia.

•increase

•What is weight?

• The force of gravity on a person or object on the surface of a planet

•How can we increase acceleration of an object?

•Decrease its mass• Increase force

•What is friction?

•The force that one surface exerts on another when the two rub together

•What is rolling friction?

•Occurs when an object rolls over another object•Example: bike tire on a road

•What is free fall?

•Occurs when the only force acting on a falling object is gravity

•Air resistance is a form of __________

•Friction

•The Law of Universal Gravitation states ____________________

•Any two objects in the universe are attracted to each other

•What is the formula for momentum

•Mass x velocity

•What is force?

•A push or pull on an object

–How can you increase momentum?

• Increase the velocity (speed) of the object• Increase the mass of the

object

•What is mass?

•The amount of material (matter) in an object

•How can you increase friction?

•Make the surfaces rougher•Example: sand on an icy sidewalk

•What is gravity?

•The force that pulls objects toward earth

•What is Newton’s third law and give an example.

• For every action there is an equal and opposite reaction

• Example: a hammer hits a nail and the nail exerts a force back on the hammer

• If forces on an object are balanced,

• The object will never change its motion (move)

• If the forces on an object are unbalanced,

•There will be a change in the objects motion

•What is the formula that describes Newton’s 2nd law of motion?

• Acceleration = net force x mass

•What are two factors that affect gravitational pull?

•Mass of the objects•The distance between the objects

• On the arrow below, what does the point of the arrow indicate?

•The direction of the force

• On the arrow below, what does the length of the arrow indicate?

•The strength of the force

• In what direction is the net force acting?

•To the left

• From what direction must force be applied so that forces are balanced?

•To the left

• If a third force is applied to the object, in what direction will the object move?

•Up and to the left