41.  Heat is:

A)  energy transferred by virtue of a temperature difference

B)  energy transferred by macroscopic work

C)  energy content of an object

D)  a temperature difference

E)  a property objects have by virtue of their temperatures

42.  Heat has the same units as:

A)  temperature

B)  work

C)  energy/time

D)  heat capacity

E)  energy/volume

43.  A calorie is about:

A)  0.24 J

B)  8.3 J

C)  250 J

D)  4.2 J

E)  4200 J

44.  An insulated container, filled with water, contains a thermometer and a paddle wheel. The paddle wheel can be rotated by an external source. This apparatus can be used to determine:

A)  specific heat of water

B)  relation between kinetic energy and absolute temperature

C)  thermal conductivity of water

D)  efficiency of changing work into heat

E)  mechanical equivalent of heat

45.  The heat capacity of an object is:

A)  the amount of heat energy to raise its temperature by 1?C

B)  the amount of heat energy to change its state without changing its temperature

C)  the amount of heat energy per kilogram to raise its temperature by 1?C

D)  the ratio of its specific heat to that of water

E)  the change in its temperature caused by adding 1 J of heat

46.  For constant volume processes the heat capacity of gas A is greater than the heat capacity of gas B. We conclude that when they both absorb the same energy as heat at constant volume:

A)  the temperature of A increases more than the temperature of B

B)  the temperature of B increases more than the temperature of A

C)  the internal energy of A increases more than the internal energy of B

D)  the internal energy of B increases more than the internal energy of A

E)  A does more positive work than B

47.  The specific heat of a substance is:

A)  the amount of heat energy to change the state of one gram of the substance

B)  the amount of heat energy per unit mass emitted by oxidizing the substance

C)  the amount of heat energy per unit mass to raise the substance from its freezing to its boiling point

D)  the amount of heat energy per unit mass to raise the temperature of the substance by 1?C

E)  the temperature of the object divided by its mass

48.  Two different samples have the same mass and temperature. Equal quantities of energy are absorbed as heat by each. Their final temperatures may be different because the samples have different:

A)  thermal conductivities

B)  coefficients of expansion

C)  densities

D)  volumes

E)  heat capacities

49.  The same energy Q enters five different substances as heat. Which of these has the greatest specific heat?

A)  The temperature of 3 g of substance A increases by 10 K

B)  The temperature of 4 g of substance B increases by 4 K

C)  The temperature of 6 g of substance C increases by 15 K

D)  The temperature of 8 g of substance D increases by 5 K

E)  The temperature of 10 g of substance E increases by 10 K

50.  A cube of aluminum has an edge length of 20 cm. Aluminum has a density 2.7 times that of water (1 g/cm³) and a specific heat 0.217 times that of water (1 cal/g?C?). When the internal energy of the cube increases by 47000 cal its temperature increases by:

A)  5 C?

B)  10 C?

C)  20 C?

D)  100 C?

E)  200 C?