physics-thermodynamics

Question 1

3 types of heat transfer

Answer 1

• heat is the energy transferrerd from one object to another due to their temperature difference, & it always flows from hotter objects to colder objects

1. Conduction: physical contact (holding coffee)/direct contact
2. Convection: flow of fluids (blow dryer)
3. Radiation: electromagnetic radiation (infrared light, sun to earth)
   
   1. radiation heat transfer is significantly only for high temp

dry ice is a solid and so is coil=conducation!

Question 2

Phase diagram

Answer 2

• During phase transition, the temperature of a substance remains constant
• the condensation point is the temp at which the phase transition from gas to liquid occurs, releasing heat equal to its latent heat of vaporization

Question 3

Constant Values

Answer 3

Question 4

The phase transition from a solid to a liquid requires ____________ to break bonds between molecules

Answer 4

• requires heat (energy); this energy is the latent heat of fusion (melting)
• when heat is added to a mixture of ice & water at 0 degree C, the heat will first go toward melting the ice before raising the temperature of the water