# Physics Exam 1

## 17 terms

### Displacement

an objects distance and direction from an earlier location. If you know an objects starting velocity and acceleration, you can calculate its displacement. Units: meters

### Speed

The rate at which an object changes its position. Units: m/s

### Vectors

Something that has both magnitude and direction. Units m/s

### average velocity

an objects average speed and direction

### Instantaneous velocity

An objects speed and direction at a particular time. Units m/s

### Acceleration

The rate at which an objects velocity changes. You can change an objects velocity by changing its speed or direction.
Units: m/s/s

### Inertia

an objects resistance to change in its velocity. the more inertia an object has the harder it is to change its speed or direction.

### Mass

A measure of an objects inertia. If an object has a large mass it has a lot of inertia. Units: kg

push or pull

### Force of gravity

the force of attraction that all objects have for each other.

### torque

the turning effect of a force. Units: meter-newton

### angular velocity

the rate at which an object is turning. units: revolutions/minute

### moment of inertia

an objects resistance to a change in angular velocity.
Units: kg x m^2

### angular momentum

the product of an objects moment of inertia and its angular velocity. Angular momentum is CONSERVED.

### 1st Law of motion

an object at rest will remain at rest, an object in motion will remain in motion at a constant velocity, unless an unbalanced force is applied to it

### 2nd law of motion

the acceleration of an object is directly proportional to the unbalanced force applied to the object and inversely proportional to the objects mass.

### 3rd law of motion

for every force applied to an object, there is another force that is exactly equal in magnitude but opposite in direction applied to the other object.