Topic 7: Efficiency Flashcards
1
Q
1st law of thermodynamics
A
Energy cannot be created or destroyed, only transformed from one form to another
2
Q
2nd law of thermodynamics
A
no energy conversion is 100% efficient, some energy is lost as heat when transforming forms
3
Q
development of steam engine
A
when water boiled, steam exerts pressure to move objects
thermal energy > kinetic energy to do work
4
Q
hydro electric dams
A
gravitational potential energy of falling water > kinetic energy to spin turbines > makes electrical energy
5
Q
coal power plant
A
chemical potential energy in coal > thermal energy to heat up water & make steam > kinetic energy to spin turbines > makes electrical energy
6
Q
efficiency calculation
A
useful energy output / energy input x 100
