Chapter 9 Definition | Chapter 9 Vocab |
The change of an object's position | Motion |
The force that keeps objects from moving against other objects | Friction |
Determined by the mass and velocity of an object | Momentum |
The speed and direction of a moving object | Velocity |
Occurs whenever an object speeds up, slows down, or changes direction | Acceleration |
Force is equal to the mass of an object an its acceleration | Second Law of Motion |
When one object exerts a force on another object, the second object reacts by exerting an equal force back on the first object. | Third Law of Motion |
An object tends to stay at the same velocity unless another force causes it to change. | First Law of Motion |
The ability to do work | Energy |
The ability to make something move | Mechanical energy |
A fixed unmoving object or location | Reference point |
The change in an object's position | Motion |
The amount of matter in an object | Mass |
Determined by an object's mass and velocity | Momentum |
A push or pull that causes an object to change speed or direction | Force |
Keeps an object from moving against other objects | Friction |
Occurs whenever an object speeds up, slows down or changes direction | Acceleration |
The resistance to a change in motion | Inertia |
Spot where a lever turns | Fulcrum |
Resistance force works against | Effort |
An example of a wheel and axle | Doorknob |
Which unit is used to measure work? | Joule |
The decrease in effort that is needed to move an object | Mechanical Advantage |
Which machine is a bar that turns on a point | Lever |
Which machine is actually an inclined plan wound around a cylinder or cone | Screw |
Which machine consists of two inclined planes placed back to back | Wedge |
Which simple machine makes work easier by either changing the direction of the force or by reducing the amount of force needed to move an object | Pulley |
Who formulated the three laws of motion | Sir Isaac Newton |
Gravity affects motion by | keeping an object frommoving indefinitely in a straight line |
Friction affects motion by | keeping objects from moving against other objects. |
Rocket launching, expelling gas downward to ground, causing rocket to move upward | 3rd Law of Motion |
Skating and hit a rock causing you to fall when you hit the rock | 1st Law of Motion |
Takes one student to carry a box of candy but takes two students to carry the same box with rocks. | 2nd Law of Motion |