Heat, Part 2

1
Heat, Part 2
2
Two objects are made of the same material, but
have different masses and temperatures. If the
objects are brought into thermal contact, which
one will have the greater temperature change?

1. The one with the higher initial temp.
2. The one with the lower initial temp.
3. The one with the larger mass.
4. The one with the smaller mass.
5. The one with the higher specific heat.

3
Two different objects receive the same amount of
heat. Which of the following choices is NOT a
reason why the objects may have different
temperature changes?

1. They have different initial temps.
2. They have different masses.
3. They have different specific heats.

4
You step out of a swimming pool on a hot day,
where the air temperature is 90 F. Where will
you feel cooler, in Phoenix or in Philadelphia?

1. Equally cool in both places.
2. Phoenix.
3. Philadelphia.

5
Answers

• 4, QmcDT They both have the same Q (heat flows
  from one to the other). If same c, then smaller
  mass means bigger DT.
• 1. The initial temp does not affect the CHANGE
  in temp, QmcDT
• 2. since its hot, the water will evaporate from
  your skin. Evaporation takes energy which comes
  from your skin (cooling your body). In Phoenix
  the air is drier and thus can absorb more water
  making the evaporation process easier and more
  likely.