Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/25

Click to flip

25 Cards in this Set

  • Front
  • Back
Newton's 3rd Law
- For every action, there is an equal and opposite reaction
-If object A pushes on object B, the object B pushes back on object A with an equal and opposite force
- Can't hit anything harder than it can hit you
Action- Reaction
Action- reaction forces don't cancel becase they're acting on different objects
Momentum
- inertia in motion
- p=mv
- units: kgm/s
-related to Newton's 1st Law
Impulse
- change in momentum
- I=^p=Ft
-Related to Newton's 1st Law
- a=F/m
^V/t=F/m
m^v=ft
^p=Ft
Follow Through
^p=Ft
^p- as big as possible
F- same
t- more time in contact
- Make force last longer
Helmets and Air bags
^p=Ft
^p- same
F- Smaller when time is less
t- longer with air bag
Law on Conservation of Momentum
The total momentum of a system remains the same unless there's an outside net force.
Pbefore=Pafter
The mometnum of a system stays the same unless a net outside force
Bouncing
- bigger than ^p than stopping
- bounce is a double impulse
Momentum Concentration
- Car and airplane crash
- Pbefore= Pafter
Work
- How energy is transferred
- How an object gains and loses energy
W=F//d
//- parallel
Nm= J
Energy
- Ability to do work (E)
- Joules
- circular definition
J
Joules
Types of Energy
Mechanical Energy
- potential energy (PE) energy due to position (work done to put the object there)
- Kinetic energy (KE) energy due to motion
Power
- Rate of doing work, rate of transferring energy
P= w/t=E/t
J/s= W (watts)
1 Watt- doing 1 J of work in 1 s
Potential Energy
Walking vs. Running up stairs
Same energy ( same work to lift body to same height)
- More power to run up
PEgrav= work required to life object to that height
=Fgravd
=(mg)(h)
Ground level
- Arbitrary Zero
- Path independent
Kinetic Energy
KE= work needed to get up to speed
v=(fd)
=1/2mv2
Econs
- The total amount of E in the universe always remains the same
Useable Energy
- KE
- PE
- Electricity
- Light
- Chemical
Un-useble Energy
- heat
Sun
- coal-dead plant- sun
- oil- dead animals-plants- sun
Heat Death
- All energy transfers always involve a confersion of some energy to heat- spreads out and done with heat
- eventually it will all be heat
Gun Bullet Example
Fgun=Fbullet
agun<abullet
agun- becuase it has more mass- more inertia, resisting more change
Earth Acc
- going towards earth
- earth coming up
- small acc because of big mass
Changing speed
-double the speed
- square the relationship (square KE)