Steel blocks A and B, which have equal masses, are at TA = 300 C ...

[bobthebuilder]

Steel blocks A and B, which have equal masses, are at TA = 300 C and TB = 400 C. Block C, with mC = 2mA, is at TC = 350 C. Blocks A and B are placed in contact, isolated, and allowed to come into equilibrium. Then they are placed in contact with block C. At that instant,
 a. TA = TB < TC.
  b. TA = TB = TC.
  c. TA = TB > TC.
  d. TA + TB = TC.
  e. TA - TB = TC.

Question 2

Duff states that equal masses of all substances have equal changes in internal energy when they have equal changes in temperature. Javan states that the change in internal energy is equal to a constant times the change in temperature for every DT, no matter how large or how small DT is, but that the constant is different for different substances. Which one, if either, is correct?
 a. Neither, because the specific heat depends on the substance and may vary with temperature. b. Neither, because a change of state may involve release or absorption of latent heat.
  c. Neither because a substance may do work during a temperature change. d. All of the statements above are correct.
  e. Only statements (a) and (b) are correct.

[macagnavarro]

Answer to Question 1

B

Answer to Question 2

D

[bobthebuilder]

Excellent

[parshano]

Gracias!