,Chapter 1 Solutions
Chapter 1 Problem Subject Areas
1.1–1.2 Applications of thermodynamics
1.3–1.14 Closed and open systems
1.14–1.31 Key concepts and definitions
1.32–1-55 Dimensions and units
1.56–1.69 Mathematics review
,Problem 1.1 Conceptual Problem.
Definition of Thermodynamics:
Thermodynamics is the science that deals with the relationship of heat and mechanical
energy and conversion of one into the other.
There are many everyday thermodynamics applications. Some examples are included in Chapter
1. Other examples include:
Coaster brake on a bicycle converts mechanical energy of the moving wheel to frictional heating.
Refrigerator requires work input to transfers energy from the cold to the hot region.
The human body converts the energy from food to body heat and movement.
Problem 1.2 Conceptual Problem.
Device Form of Energy Input Form of Energy Output
Toaster Electrical energy Heat transfer from the hot
metal strips
Air conditioner Electrical energy Heat transfer from cold to hot
regions
Light bulb Electrical energy Heating of bulb by electrical
resistance of the filament
Clothes iron Electrical energy Heat transfer
Refrigerator Electrical energy Heat transfer to kitchen
Problem 1.3 Conceptual Problem.
A closed and open system can have:
a change of internal energy within the system
heat transfer in or out of the system at the system boundary
work transfer at the system boundary
a change in the volume of the system
Only an open system will have mass entering or leaving the system.
, Problem 1.4 Conceptual Problem.
Hand pump inflating a bicycle tire.
Closed Systems
rubber tire (not including air)
spokes of tire
handle of pump
Open Systems
open system around the tire the includes air entering
the tire.
Open system around pump that includes air entering
and exiting the pump as the handle is pumped.
Open system around the hose that include air flow
in and out
Problem 1.5 Conceptual Problem.
Using Figure 1.22,
An open system can be drawn to include only the air in the
balloon and not the rubber balloon. As the balloon deflates,
air will leave the new open system.
A closed system can be defined as the rubber balloon only
without air.
A closed system can be defined as a fixed mass of air that
moves from the inside to the outside of the balloon and can
also change in volume.
Chapter 1 Problem Subject Areas
1.1–1.2 Applications of thermodynamics
1.3–1.14 Closed and open systems
1.14–1.31 Key concepts and definitions
1.32–1-55 Dimensions and units
1.56–1.69 Mathematics review
,Problem 1.1 Conceptual Problem.
Definition of Thermodynamics:
Thermodynamics is the science that deals with the relationship of heat and mechanical
energy and conversion of one into the other.
There are many everyday thermodynamics applications. Some examples are included in Chapter
1. Other examples include:
Coaster brake on a bicycle converts mechanical energy of the moving wheel to frictional heating.
Refrigerator requires work input to transfers energy from the cold to the hot region.
The human body converts the energy from food to body heat and movement.
Problem 1.2 Conceptual Problem.
Device Form of Energy Input Form of Energy Output
Toaster Electrical energy Heat transfer from the hot
metal strips
Air conditioner Electrical energy Heat transfer from cold to hot
regions
Light bulb Electrical energy Heating of bulb by electrical
resistance of the filament
Clothes iron Electrical energy Heat transfer
Refrigerator Electrical energy Heat transfer to kitchen
Problem 1.3 Conceptual Problem.
A closed and open system can have:
a change of internal energy within the system
heat transfer in or out of the system at the system boundary
work transfer at the system boundary
a change in the volume of the system
Only an open system will have mass entering or leaving the system.
, Problem 1.4 Conceptual Problem.
Hand pump inflating a bicycle tire.
Closed Systems
rubber tire (not including air)
spokes of tire
handle of pump
Open Systems
open system around the tire the includes air entering
the tire.
Open system around pump that includes air entering
and exiting the pump as the handle is pumped.
Open system around the hose that include air flow
in and out
Problem 1.5 Conceptual Problem.
Using Figure 1.22,
An open system can be drawn to include only the air in the
balloon and not the rubber balloon. As the balloon deflates,
air will leave the new open system.
A closed system can be defined as the rubber balloon only
without air.
A closed system can be defined as a fixed mass of air that
moves from the inside to the outside of the balloon and can
also change in volume.
