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physics/Work Energy and Power/Potential Energy.md

@@ -1,7 +1,7 @@
 [[Work Energy and Power]]
 megumi energy
 
-# SUMMARY
+# Summary
 * potential energy refers to multiple objects in a system affecting each other with conservative forces
 * In MY words, potential energy is j stored kinetic energy that something has due to its surroundings, and it cashes it out and converts the PE to KE.
 * Scalar
@@ -10,7 +10,7 @@ megumi energy
 * Gravitational potential energy between 2 spherical masses: $U_g=-G\frac{m_1m_2}{r}$. Near surface approximation: $\Delta U_g=mg\Delta y$
 * For a system with more than 2 objects, potential energy is sum of energy of every pair.
 
-## Zero Potential Energy Definition
+# Zero Potential Energy Definition
 * Can define zero PE as any convenient reference point
 * For gravitational PE, a common ref point is ground level.
 * Springs equilibrium is the natural zero PE point.

physics/Work Energy and Power/Power.md

@@ -0,0 +1,24 @@
+[[Work Energy and Power]]
+
+Power is how fast energy moves or changes form.
+
+# Summary
+* SI Unit is Watts (W), where 1 W = 1J/s
+* Average power is energy change over time: $P_{avg}=\frac{\Delta E}{\Delta t}$. Work changes energy so $P_{avg}=\frac{W}{\Delta t}$
+* Instantaneous power for a constant force: $P_{inst}=F_{||}v=Fv\cos \theta$ using only force component parallel to velocity.
+* Sign of power tells direction, positive means energy added negative means energy removed.
+* When an object moves at a constant speed, energy is zero.
+
+# Average Power Calculation
+$$P_{avg}=\frac{\Delta E}{\Delta t}$$
+Examples:
+* 60 watt light bulb transfers 60 joules into light and heat.
+* 1500 watt hair drier running for 5 minutes transfers 1500 * 300 watts.
+* Solar panel generating 500 watts per second stores 500 joules to be used later.
+
+# Power as Work Rate
+$$P_{avg}=\frac{W}{\Delta t}$$
+Power can be calculated by dividing work by time taken.
+
+# Instantaneous Force from Power
+$$P_{inst}=F_{||}v=Fv\cos \theta$$

physics/Work Energy and Power/Work.md

@@ -7,7 +7,7 @@
 * Conservative forces do path independent work that is zero in a full loop and stays the same no matter what path is taken to the endpoint (e.g. gravity) while non-conservative forces care about the path taken (e.g. air resistance).
 * Net work = $\Delta K = \Sigma W_i$
 
-## Conservative vs Non Conservative
+# Conservative vs Non Conservative
 * Potential energy is conservative only
 * examples of conservative are gravity and spring
 * Conservative essentially means the work done only changes mechanical energy