22. Thermodynamics [Heat]

Question 1

What is heat?

Answer 1

Heat is thermal energy that transfers from one object to another when they are at different temperatures. This is just a transfer of energy so its units are joules.

Question 2

How can you generate heat?

Answer 2

Any type of energy can be transformed into heat. Work done to overcome friction is often partially transformed into heat. This is why your hands get warm when you rub them together.

Question 3

What are the units for the transfer of energy or heat?

Answer 3

1. Joules
2. Calories

Question 4

How much joules are there in a calorie?

Answer 4

1 calorie = 4.18J
1000 calories = 4,184 J

Question 5

What are the 2 equations for Heat (Mr. Shockley discussed)?

Answer 5

Q = mcΔT or Q = mc(T_f - T_i)

Question 6

What does all the symbols in [Q = mcΔT or Q = mc(T_f - T_i)] stands for? Include its units.

Answer 6

Q stands for heat and the units of heat are joules.

m stands for mass and the unit for mass are Kg.

Δ is the greek letter delta and it stands for a change in temperature: this has not units.

T stands for Temperature and the unit we use in this equation is celsius.

c stands for the specific heat of a material and has the unit J/Kg*C.