Heat is defined to be A. The amount of microscopic
translational and rotational kinetic energy in an object B. Energy
that is transferred to an object because of a temperature
difference C. The temperature of an object in terms of degrees
Kelvin.
Slide 2
Energy transferred (Q)
Slide 3
200 g of water at 100 o is poured into 200 g of water at 0 o.
The resulting temperature will settle down to be A. 0 o B. 50 o C.
100 o D. Greater than 50 o but less than 100 o E. Less than 50 o
but more than 0 o
Slide 4
Slide 5
c water =4186 J/kg o C c gold =129 J/kg o C I use a heating
element to put heat into a kg of water and a kg of gold at the same
rate. Which changes temperature faster? A. 1 kg water B. 1 kg gold
C. They both heat up at the same rate. Q is energy transferred
Slide 6
Slide 7
Put 100g Al at 100 o C into 500g water at 20 o C. What is the
final T? What will the final T be? 1. 100 o 2. 97 o 3. 20 o 4. 23 o
5. 60 o c Al = 900 J/kg o C c H2O = 4186 J/kg o C
Slide 8
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Slide 10
You put 0.4 kg of lead into a bucket containing 1.2 kg of pure
acetone. Why in the world did you do that?
Slide 11
Idolatry (Even non-believers find something to believe in) "As
I study ancient scripture, I am more and more convinced that there
is significance in the fact that the commandment 'Thou shalt have
no other gods before me' is the first of the Ten Commandments." -
President Spencer W. Kimball (Aug 1977 Ensign)
Slide 12
It also takes energy to melt a solid or turn a liquid into gas
Latent heat of fusion vs. vaporization
Slide 13
You place equal weights of ice (at 0 o C) and boiling water (at
100 o C) into a well-insulated container. What is the final
temperature. A. 0 o C B. Between 0 o and 50 o C C. 50 o C D.
Between 50 o C and 100 o C L f 3.33x10 5 J/kg L v 2.26x10 6 J/kg
cice2090 J/kg o C water 4186 J/kg o C steam 2010 J/kg o C
Slide 14
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Slide 17
You place a mass m i at temperature T i into a mass m w of
water at temperature T w. What will be the final temperature, and
how much ice will there be?
Slide 18
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Slide 20
You place equal weights of ice (at -20 o C) and water (at 0 o
C) into a well-insulated container. How much boiling water must be
added to produce only water at 0 o C.
Slide 21
L f 3.33x10 5 J/kg L v 2.26x10 6 J/kg cice2090 J/kg o C water
4186 J/kg o C steam 2010 J/kg o C
