2: Energy Flashcards
What is energy?
the ability to do work or to cause a heat transfer between objects
What are types of energy?
- thermal energy
- radiant energy
- light energy
- chemical energy
- nuclear energy
- electrical energy
- gravitational energy
- mechanical energy
What is chemical energy?
energy stored in the chemical bonds of molecules
What is a calorie?
unit of energy/energy stored in the food
What is low quality energy?
it is very dispersed and hard to gather; often in the form of heat
What is high quality energy?
it is very concentrated and easy to use
What are examples of high quality energy?
chemical energy in oil, electricity, food
What are examples of low quality energy?
heat in the Atlantic Ocean, heat dispersed into the atmosphere
What is the first law of thermodynamics?
aka: law of conservation of energy
energy is neither created nor destroyed but transformed from one form to another
What is the second law of thermodynamics?
in any conversion of energy from one form to another, some of the initial energy input is always degraded to lower quality, less useful energy, usually low temperature heat that flows to the environment
What is the external energy source that keeps all biological processes running?
the SUN
What is earth’s energy budget?
- 30% radiated back by clouds, chemicals, and dust in the atmosphere
- 70% warms land and atmosphere, evaporates water and causes winds
- 0.023% captured by plants (photosynthesis)
What happens to energy?
energy can be converted from one form to another but with each conversion, energy quality is lost (quantity is still the same)
