Energy and Power in Engineering
Every machine an engineer builds does one thing at its heart: it moves energy from one place or form to another. A car turns fuel into motion. The Toktogul dam turns falling water into electricity that lights up Bishkek. A phone charger turns wall electricity into stored chemical energy in a battery. Once you can follow the energy through a design, you can understand almost any machine ever made.
- Explain what energy and work are, and calculate work as force times distance (in joules).
- Explain what power is and why doing the same job faster needs more power (in watts).
- Name the main forms of energy engineers work with, and trace how one form turns into another.
- Use the conservation of energy to always ask "where did the energy go?"
- Calculate efficiency and understand why no machine is ever 100% efficient.
- Read an electricity bill in kilowatt-hours and work out the cost of running an appliance.
- Compare the main energy sources used in engineering, including why hydropower is Kyrgyzstan's treasure.
Energy is the ability to do work — to make something move, heat up, light up, or change. Anything that can push, pull, lift, spin, warm, or shine has energy. A stretched rubber band has energy (it can snap back and fling a paper ball). A litre of petrol has energy (it can drive a car for a kilometre). Hot tea has energy (it can warm your hands). A river high in the Tien Shan mountains has energy (it can crash down and spin a turbine).