Module 1 : POWER and ENERGY
OBJECTIVES:
By the end of this lecture, the students will be able to:
• Explain the difference between power and energy.
• Review the basic physical quantities describing the state of a fluid substance
• Review the Metric SI and the English unit systems.
• Learn current energy capacities and consumptions in the Philippines and the
world.
• Able to solve review problems on power and energy.
Energy is the ability to do work
Forms of Energy
Types of Energy
 Heat (thermal)
 Chemical
•Stored (potential) energy
 Light (radiant)
 Nuclear energy
•Working (kinetic) energy
 Motion (kinetic)
 Gravitational
 Electrical
Energy sources
Renewable
an energy source that
can be easily replenished
•Solar energy from the sun
•Geothermal energy from heat inside the earth
•Wind energy
•Biomass from plants
•Hydropower from flowing water
Nonrenewable
an energy source that cannot
be easily replenished
•Petroleum products
•Hydrocarbon gas liquids
•Natural gas
•Coal
•Nuclear energy
For the Philippines…
See the attached files…
Power is the rate at which energy is
produced or consumed
Associated with mechanical and electrical forms of energy
PROPERTIES:
Basic physical quantities describing the state of a fluid substance
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Pressure
Volume
Temperature
Enthalpy
Entropy
Other properties:
 Specific Heat
 Density
 Internal Energy
Review problems:
 A force of 45kg pushes a body to move horizontally at a distance of 4 meters at a uniform
speed of 2 m/min. If the force is applied at an angle of 30o to the horizontal, what is the work
done? And the power?
 A shaft rotating at 1200 rpm receives an applied torque of 80 kg-m. What is the received
metric horsepower?
 A water jet which is 5 cm in diameter emerges from a nozzle with a velocity of 230 m/s. Find
the power produced by the water jet.
 A rotating turbogenerator rotor has a total weight of 11,000 kg and a composite radius of
gyration of 50 cm. The rotative speed is 1800 rpm. Find the energy produced.
Review problems:
 A 1400 kg automobile is running with a speed of 72 kph, how much energy is possessed or
stored ?
 An elevator weighing 700 kg rises from the first floor (grade 0.00m) to fifth floor (grade
14.8m). Find the energy associated with this rise?
 How much potential power can be developed in a river flow of 5m3/s at a site where a 40m
head is available?
END