Question

QUESTION 1 If you do 1,000 J of work on a system and remove 500 J of heat from it, what is the change in its internal energy?

a.-1,500 J
b.-500 J
c.1,500 J
d.500 J

QUESTION 2 The first law of thermodynamics is related to the conservation of which quantity?
a.matter
b.heat
c.work
d.energy

QUESTION 3 Which of the following devices does not convert heat energy to mechanical energy?
a.internal combustion engine
b.windmill
c.steam turbine
d.coal-fueled power plant 

QUESTION 4 Which of the following statements correctly describes a heat engine?
a.Work is used to transfer thermal energy from a hot reservoir to a cold one.
b.Work is done by transferring thermal energy from a cold reservoir to a hot one. c.Work is used to transfer thermal energy from a cold reservoir to a hot one.
d.Work is done by transferring thermal energy from a hot reservoir to a cold one.

QUESTION 5 How much work can be extracted from 5.00 × 104 J of heat when 2.00 × 104 J of heat is exhausted?
a.7.00 × 104 J
b.3.00 × 104 J
c.3.00 × 104 J
d.7.00 × 104 J

QUESTION 6 Which of the following statements would best describe how to increase the work done by a heat engine?
a.Raise the temperature of the exhaust.
b.Raise the temperature of the cold reservoir.
c.Lower the temperature of the exhaust.
d.Lower the temperature of the hot reservoir.

Answer 1

Sallyablow has them all correct except 4 and 6.

4. D
6. C

Answer 2

1. U = Q + W
U = -500 + 1000
U = 500 J

2. The first law of thermodynamic is about the law of conservation of energy where energy in should be equal to energy out.

3. It is the windmill that does not transform energy from heat to mechanical instead it is the transforms the opposite.

4. In a heat engine, work is used to transfer thermal energy from a hot reservoir to a cold one.

5. 5.00 × 10^4 J - 2.00 × 10^4 J = 3.00 × 10^4 J

6. To increase the work done, we raise the temperature of the cold reservoir.