MOON'S WORLD
Home
Labs
Unit 1
>
Buggy Lab
Cart on a Ramp Lab
Cart on Ramp Lab
Unit 2
>
Unbalanced Forces lab
Unit 3
>
Whirly Durly Lab
Content
Unit 1- Kinematics
Unit 2- Forces
Unit 3-circular motion
Unit 4- Energy
Unit 5- Momentum
About
Contact
Unit 1
Physics of Something
Representing Energy Transfers with Bar Charts
1st L: initial energy before the event
O: system
2nd L: final energy after the event
Tips:
remember to state the correct system- eg if earth is not in the system, there is NO gravitational potential energy
don't think too complicated- it is what it is
draw the AMOUNT of energy transfer in/out of the system as barred arrows at the "O"
Energy Problem Solving
read question and determine the general ENERGY CONSERVATION EQUATION
Eint + W + Q + R = Efin
determine the variable we need to find
draw LOL chart
list specific equation and solve for x
Work
energy can be transferred by an external PUSH/PULL
you ADD energy to it (unless ur part of the system- then energy just transfers)
if there is displacement, there is work
if there is DISTANCE but no displacement, you have work in opposite directions of same magnitude, so Wfin =0
general equation: W= F*delta x
Power
the RATE of energy transfer
W/delta t
units of measure= Watts (W) = J/s
Horse power
amount of work a horse can do in a day
Relating energy/work/power to forces and motion
Common sense:
you need energy to do work
when you do work, you exert some kind of force/influence motion
how "powerful" you are depends on your work efficiency
Equations
K = 1/2 m*v^2
Us = 1/2 k*delta x^2
k = spring constant
delta x = spring stretched/compressed distance ONLY
Ug = m*g*h (delta x)
g = 9.8m/s usually
Connecting reps of motion with reps of forces with reps of energy
Law of CONSERVATION
Area under:
force-time graph: change in energy
velocity-time graph: distance traveled displacement
acceleration-time graph: velocity
Reps of motion/forces/energy stated as in previous sections
ALL interconnected
Home
Labs
Unit 1
>
Buggy Lab
Cart on a Ramp Lab
Cart on Ramp Lab
Unit 2
>
Unbalanced Forces lab
Unit 3
>
Whirly Durly Lab
Content
Unit 1- Kinematics
Unit 2- Forces
Unit 3-circular motion
Unit 4- Energy
Unit 5- Momentum
About
Contact
Unit 1
Physics of Something