# Matthew Hursky, Brendan Donovan, Jacob Day, Vivian Zhang.

## Presentation on theme: "Matthew Hursky, Brendan Donovan, Jacob Day, Vivian Zhang."— Presentation transcript:

Matthew Hursky, Brendan Donovan, Jacob Day, Vivian Zhang

* Thermodynamics: the study of heat and its transformation into mechanical energy * Internal energy: amount of thermal energy within an object * Heat flows between objects, thermal energy resides in objects, temperature is a measure of average kinetic energy

* Conduction: heat transfer through objects touching * Atoms collide and transfer energy * Heat is transferred until the objects are at thermal equilibrium (same temperature)

* Convection: heat transfer through moving currents in gases/liquids * Hot gases and hot liquids rise, creating convection currents

* Radiation: heat transfer through electromagnetic radiation * No matter necessary * Can occur in a vacuum

heat added increase in internal energy external work done by the system = +

* Adiabatic process: when a gas is compressed or expanded so that no heat enters or leaves a system * Isothermal process: when the temperature of the system remains constant

* Heat always flows from warmer objects to colder objects

* Heat engine: a device that changes internal energy (heat) into mechanical work * Based on heat flowing from high temperature area (reservoir) to low temperature area (sink)

* No system can reach absolute zero

* Entropy: amount of disorder in a system * Entropy tends to increase (2 nd Law of Thermodynamics) * Decreasing the entropy of a system requires work

* The input heat in a heat engine is 600K(227 C) and the output is 300K(77 C). It’s ideal efficiency is: * A) 25% * B) 50% * C) -50% * D) 80%

* How many calories are required to raise the temperature of 16 grams of water by 10 degrees C? * A) 100 calories * B) 120 calories * C) 160 calories * D) 200 calories

* What is the rise in temperature when 20 calories are added to 10 grams of ice at -10 degrees C? Specific Heat of Ice:.5Cal/Grams X C * A) 8 degrees C. * B) 16 degrees C. * C) 4 degrees C. * D) 2 degrees C.

* Ann is making pancakes. She burns her hand by touching the pan. What method of heat transfer explains this? * A) Conduction * B) Thermal Radiation * C) Convection * D) None of the above

* How do you increase the internal energy of an object? * A) Heat the system * B) Do work on the system * C) Both A & B * D) None of the above

* The First Law of Thermodynamics states that: * A) when heat is added to a system, it will be lost * B) when heat is added to a system, it will be transformed into twice as much energy * C) when heat is added to a system, it will be transformed into an equal amount of energy * D) adding heat is the only way to increase the internal energy of a system

* Heat will flow: * A) from cold to hot * B) always upwards * C) from hot to cold * D) always downwards

* The most efficient heat engine is one with: * A) the smallest difference between input and output temperature * B) a large difference between input and output temperature * C) low input temperature and low output temperature * D) high input temperature and high output temperature

* The natural tendency of particles in a system is to: * A) separate from different particles in the system * B) continue moving in a straight line no matter what * C) rapidly travel in small spirals * D) create greater disorder

* How is thermal energy transported from one place to another? * I. Conduction * II. Convection * III. Radiation A) I only B) I and II only C) II only D) I, II and III

1) B 2) C 3) C 4) A 5) C 6) C 7) C 8) B 9) D 10) D