# physics

The flashcards below were created by user JustDoughnut on FreezingBlue Flashcards.

1. fundamental unit
basic units from which all other units are made
2. derived unit
units that are a combination of two or more of the fundamental units
3. converesions
1 hr = 3,600 s

1km = 1,000 m
4. to change an object's motion you need __ __.
the change an object's motion you need unbalanced forces.
5. constant or no motion means __ __.
constant or no movement means balanced forces.
6. three ways to describe motion
• words
• math
• graphs
7. reference point
"zero" location in a frame of reference
8. frame of reference
a number line used to describe motion
9. position
separation between the object and reference point
10. scalar quantity
• quantity that only has size/magnitude
• # and unit
• distance is scalar
11. vector quantity
• quantity that has size, magnitude and direction
• #, unit and direction
• acceleration, position, displacement, velocity
12. instantaneous position
position at a certain time
13. distance (d)
• measures the separation between two objects
• needs no reference point
• scalar quantity
14. displacement (Δd)
• change in position of an object (start point to end point)
• vector quantity
15. average velocity (v wit line)
the displacement of an object divided by the time interval over which it moved.
16. If the average velocity is the same throughout the time interval then we have __ __.
If the average velocity is the same throughout the time interval then we have constant velocity.
17. Speed vs. Velocity
speed: distance divided by time; scalar quantity

velocity: displacement divided by time; vecotr quantity
18. acceleration
the rate of change of velocity; change of velocity divided by time.

19. velocity-time graphs
• the slope of a velocity-time graph represents acceleration.
• the area under a velocity-time graph represents displacement (vector quantity).
20. distance-time graphs
the slope of a position-time graph represents velocity (speed).

21. linear motion
motion that occurs in  straight line
22. equation for constant acceleration
23. equation for when acceleration is constant and we do not have final velocity
24. equation used when acceleration is constant and you do not have time
25. summary of three equations
no displacement :

no final velocity :

• no time :
 Author: JustDoughnut ID: 237245 Card Set: physics Updated: 2013-09-26 19:56:35 Tags: physics Folders: Description: physics. Show Answers: