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09 Chat 9 motion


Force a push or pull
Newton the SI unit for force
Unbalanced force causes an object's motion to change
Balanced forces never change the object's motion
Friction the force that one surface exerts on another when the two rub against each other
Gravity the force that pulls falling objects toward Earth
Mass the amount of matter in an object
Weight the force of gravity on a person or object on the surface of a planet
unit of force, a newton, is equal to kilogram times meter per second squared
An object in free fall accelerates until it reaches terminal velocity
Objects falling through air experience a type of friction called air resistance
Inertia the tendency of an object to resist change in its motion
Momentum the product of an object's mass and velocity
Law of Conservation of Momentum when two objects collide in the absence of friction, momentum is not lost
Friction acts in a direction opposite to the direction of an object's motion
Centripetal Force any force that causes an object to move in a circle
Velocity the momentum of an object in the same direction
Forces can be added together only if they are acting on the same object
A rocket can lift off into space if the thrust is greater than Earth's gravity
The greater the mass of an object the greater its inertia
When two forces act in the same direction the forces are added together
Law of Universal Gravitation any two objects in the universe attract each other
Satellite an object that travels around another object in space