1. Wednesday 8 October 2014 Read: –Section 3.1. Problems: –3.2, 3.4, 3.6.

2. Physics Quantum Mech. + Special Relativity Thermo- dynamics Mechanics Electricity& Magnetism First Law EnergyHeatWork System/State

3. Surrounding What is System and what else?! System Process

4. Okay we know now what is system but what are the types of systems ? OPEN CLOSED ADIABATIC System CLOSED ISOLATED

5. Next let us learn about the concept of STATE! Positions + Velocities = State of the system (Mechanics) Experimental properties = Pressure + Temperature + Volume + Composition = Thermodynamic State of the system Extensive State α Mass => Mass, Volume Intensive State α Mass => Temperature, Pressure, Density

6. Work again! w = ∫ F. dr w = ∫ F cos ɵ dr If anti-parallel and constant F, w = F cos( π) ∫ dr w = -F Δr F =mg r Mechanical workElectrical work + + w = ∫ F. dr w = ∫ QE. dr w = Q ∫ E. dr w = ∫ F. dr w = ∫ F cos ɵ dr w = (P ext A) cos( π) ∫ dr P-V work P ext w = -P ext A Δr = - P ext ΔV w = Q φ If continuous charge distribution, w = ∫ φ dQ

7. Some HEAT and sign convention! System Work is -ve Heat is -ve Work is +ve Heat is +ve P-V work P ext

8. Now, ENERGY! ENERGY OF THE UNIVERSE IS CONSTANT, WHY ? System Surrounding E Universe E Surrounding E System Constant ΔE Universe ΔE Surrounding ΔE System 0 0 ΔE Surrounding

9. More ENERGY and some MONEY! Law of conservation of energy: Total energy of isolated system is conserved. Energy can not be created or destroyed but only change form. Lets Talk Money! h1h1 h2h2 2H 2 O (l)  2H 2 (g) + O 2 (g)

10. Sample Problem A hiker weighing 170 lbs hiked up from the Colorado River to the rim of the Grand Canyon (4,620 ft). How energy does this require? Convert this to how many Calories the hiker “burned” from the vertical hike alone? Some Units 1.00 kg = 2.20 lbs 1.00 m = 3.28 ft 1J = kg·m 2 ·s -2 (= N·m)