17.2 Flashcards
What is heat?
Energy transferred from one object to another because of the difference in their temperatures.
What is temperature?
Measure of average kinetic energy of atoms or molecules in a substance.
What happens when energy is transferred to molecules in the air?
They move faster, causing air temperature to rise.
What happens when air transfers energy to a cooler object?
Molecules move slower, causing temperature to drop.
What are the three mechanisms of energy transfer between Earth’s surface and atmosphere?
Conduction, convection, and radiation.
What is conduction?
Transfer of heat through matter by molecular activity.
How does conduction occur?
Energy of molecules is transferred by collisions from one molecule to another.
What is convection?
Transfer of heat by mass movement or circulation in a substance.
How does convection occur in fluids?
Atoms/molecules move freely, causing warmer, less dense water to rise and cooler water to sink.
What is radiation?
Energy that travels in all directions from a source and can occur through a vacuum.
What are the four laws governing radiation?
- All objects emit radiant energy. 2. Hotter objects radiate more energy. 3. Hottest bodies produce shortest wavelengths. 4. Good absorbers are good emitters.
What is the electromagnetic spectrum?
All different electromagnetic waves, including visible light, radiant heat energy, and ultraviolet waves.
What is visible light?
The only portion of the EM spectrum that is visible.
What happens when radiation strikes an object?
- Some energy is absorbed, increasing temperature. 2. Some is transmitted without adding energy. 3. Some may bounce off.
What is reflection?
When an electromagnetic wave bounces off an object without losing energy.
What is scattering?
Produces a larger number of weaker rays that travel in different directions.
Why does blue light scatter more than other colors?
Because it travels as shorter, smaller waves.
What is absorption in the context of solar energy?
50% of solar energy reaches Earth’s surface and is absorbed.
What is the greenhouse effect?
Atmospheric gases absorb energy and reradiate it back to Earth to maintain a more constant surface temperature.
What is photosynthesis?
Incoming solar radiation absorbed by plants, algae, and phytoplankton for photosynthesis.
What is acid rain?
A form of air pollution formed by sulfur dioxide and nitrogen oxide combining with moisture in the air.
What is the pH scale?
Used to describe how acidic a solution is.
What are the pH ranges for weak acids, strong acids, and neutral solutions?
Weak acids: 5-6, Strong acids: 1-2, Neutral: 7.
How does acid rain affect soil?
It removes nutrients, lowering plant resistance to diseases and bad weather.
