Light definitions (4)
What is natural light?
Light that is produced by things in nature, such as the Sun.
How do eye glasses work?
They refract light.
What part of your eye does the sun damage?
Retina
Also works: cornea, lens
What is the law of conservation of energy?
States that energy cannot be created or destroyed, only transformed
Give an example of electrical energy.
Static electricity, Lightning, Generator, a lamp plugged in
What is artificial light?
light from things made by humans, usually powered by electricity or gas.
Too much artificial light is called...
Light pollution
Does this reflect, refract or absorb light?
Water in a cup
Refract
What type of energy is energy that moves an object?
Mechanical energy
What is the input energy of a human? What is the output energy?
Input: Chemical (we digest food using the calories for energy)
Output: Mechanical (we can move - run, jump), thermal (keeps us warm - don't eat enough you can't make heat)
Materials allow light to pass through. Clear glass
Transparent
Light travels in straight paths called...
light waves
What is the speed of light?
300,000 km/second
What type of energy is energy from the movement of particles and creation of heat?
Thermal energy
What is the input and output energy of a flashlight?
Input: Chemical (use batteries, which use a chemical reaction to work)
Output: Radiant
Materials do not allow any light to pass through. Examples include wood, a metal spoon, and a cardboard box.
When light passes through an object and bends.
- Absorption, reflection, refraction
Refraction
What country has the most light pollution?
Singapore
What type of energy is energy that travels in waves, such as visible light or x-rays?
Radiant
What is the input energy and output energy of a solar panel?
Input: Radiant (uses the light from the sun)
Output: Electrical (generates electricity
Materials allow some of the light to pass through. Tissue paper and sunglasses are examples
Transluscent
When light stops at the object, what is it called?
-Reflection, absorption, refraction
Absorption
What is light?
Electromagnetic energy that our eyes can detect.
What type of energy is energy stored in bonds of atoms and molecules, often released when heated?
Chemical energy
What kind of energy is stored in the nucleus of an atom, and is released when the nuclei are combined or split?
Nuclear energy