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Quiz 14; Problems 1,2, 7, 9, 10, 12, 13, 14, 21, 24, 25, 33, 34, 35

TURN IN: 2, 10, 12, 14, 24, 30, 34

error log #1: 12/18/2010 08:39:32 PM Problem 24 has been corrected . Use the specific heat of ICE.

2. heat = m*C*(change in T). Use the specific heat of water. Use 1.0 kcal/(g^oC) . Change in temperature, mass m and heat are given.

10.

heat = m_cu*C_cu*(change in T).
heat = m_al*C_al*(change in T).
heat = m_W*C_W*(change in T).
The heat and change in temperature are the same, so find the ratios requested.

12.
|heat lost| = |heat gained|
The differences will chosen to make both sides positive.

m_cu*C_cu*(285 - T_f) = m_al*C_al*(T_f - 12) + m_W*C_W*(T_f - 12).
Find the final temperature.

14. m*C*(330 - T_f) = m_al*C_al*(T_f - 12.5) + m_W*C_W*(T_f - 12.5) +m_gl*C_gl*(T_f - 12.5) . Solve for C.

24. m*Lv = m_ice*C_ice*(273 - 77). Find m = mass of liquid nitrogen vaporized, the amount of vapor formed.

30. See quiz 6 part 2.
(1/2) mv₁² + PE₁ = (1/2)mv₂² + PE₂ + HEAT
(1/2) mv₁² = HEAT, since the other quantities are zero.
Set HEAT = m*L_f .

34. Repeat the problem with T₂ = -14.0 ^oC.

error log #1: 12/18/2010 08:39:32 PM Problem 24 has been corrected . Use the specific heat of ICE.