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Heat is defined to be. The amount of microscopic translational and rotational kinetic energy in an object Energy that is transferred to an object because of a temperature difference The temperature of an object in terms of degrees Kelvin. Energy transferred (Q).
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Heat is defined to be • The amount of microscopic translational and rotational kinetic energy in an object • Energy that is transferred to an object because of a temperature difference • The temperature of an object in terms of degrees Kelvin.
200 g of water at 100o is poured into 200 g of water at 0o. The resulting temperature will settle down to be • 0o • 50o • 100o • Greater than 50o but less than 100o • Less than 50o but more than 0o
cwater=4186 J/kg oCcgold=129 J/kg oCI 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? • 1 kg water • 1 kg gold • They both heat up at the same rate. Q is energy transferred
Put 100g Al at 100o C into 500g water at 20o C. What is the final T?What will the final T be? • 100o • 97o • 20o • 23o • 60o cAl= 900 J/kg oC cH2O = 4186 J/kg oC
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?
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)
It also takes energy to melt a solid or turn a liquid into gas Latent heat of fusion vs. vaporization
You place equal weights of ice (at 0o C) and boiling water (at 100o C) into a well-insulated container. What is the final temperature. • 0o C • Between 0oand 50o C • 50o C • Between 50o Cand 100o C Lf 3.33x105 J/kg Lv 2.26x106 J/kg c ice 2090 J/kg·oC water 4186 J/kg·oC steam 2010 J/kg·oC
You place a mass mi at temperature Ti into a mass mw of water at temperature Tw. What will be the final temperature, and how much ice will there be?
You place equal weights of ice (at -20o C) and water (at 0o C) into a well-insulated container. How much boiling water must be added to produce only water at 0o C.
Lf 3.33x105 J/kg Lv 2.26x106 J/kg c ice 2090 J/kg·oC water 4186 J/kg·oC steam 2010 J/kg·oC