Heat is defined to be A. The amount of microscopic translational and rotational kinetic energy in an...

Preview:

Citation preview

  • Slide 1
  • 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
  • Slide 9
  • 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
  • Slide 15
  • Slide 16
  • 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
  • Slide 19
  • 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
  • Slide 22
  • Slide 23

Recommended