click below
click below
Normal Size Small Size show me how
09 Chat 9 motion
motion
| Question | Answer |
|---|---|
| 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 |