A temperature of 273°C (or 0 K), at which all molecular motion stops; the lowest possible temperature.
absorption line spectrum
Dark lines superimposed on a continuous spectrum.
The smallest particle of an element that has the properties characterizing that element.
The number of protons in the nucleus of an atom of a particular element.
An emission or absorption line in the spectrum of hydrogen caused by an electron transition between the second and higher energy levels.
The entire pattern of Balmer lines.
A hypothetical perfect radiator that absorbs and re-emits all radiation falling upon it.
The intensity of radiation emitted by a blackbody plotted as a function of wavelength or frequency.
The radiation emitted by a perfect blackbody.
A decrease in the wavelength of photons emitted by an approaching source of light.
In the model of the atom described by Niels Bohr, the only orbits in which electrons are allowed to move about the nucleus.
a wave that consists of electric and magnetic fields that vibrate at right angles to each other.
transfer of energy as electromagnetic waves.
all of the frequencies or wavelengths of electromagnetic radiation.
Waves in the electromagnetic spectrum.
Radio Waves, microwaves, infrared, visible light, ultraviolet, x rays, and gamma rays.
When were x rays discovered?
What does ultraviolet mean?
It means beyond violet.
What does infrared mean?
It means below red.
How are gamma rays sometimes produced?
By some nuclear reactions.
What waves are used to make radio and tv stations?
What does FM stand for?
What does AM stand for?
Can radio waves be heard?
No. But radio waves can carry energy that can be converted into sound.
How is AM better than FM?
AM is better than FM because AM have longer wavelengths than FM wavelengths and AM waves can bounce off the atmosphere and thus can travel farther.
How is FM better than AM?
FM is better than AM because FM waves are less affected by electrical noise than AM radio waves. So, music broadcast from FM stations sounds better than a music broadcast on an AM station.
What waves do cell phones use?
What uses microwaves?
Cell phones, microwaves, and radar.
What does radar stand for?
RAdio Detection And Ranging.
What can radar do?
1.) Help ships navigate at night.
2.) Watches the movement of airplanes.
3.) To detect the speed of cars.
Which modulation does a tv use? (FM or AM)
A tv uses both frequency modulation and amplitude modulation.
How does infrared waves make you warm on a sunny day?
The infrared waves (in this case, the sun) hit your body and your skin absorbs it. Then, the energy of the waves causes the particles in your skin to vibrate more making you warmer.
Give 4 examples of things that give off infrared waves.
1.) The sun
How are infrared waves determined?
By the object's temperature.
Which give out more infrared waves?
Warmer objects do opposed to cooler objects.
Can you see infrared waves?
What can detect infrared waves?
Infrared binoculars change infrared waves into light that you can see.
Is visible light a very narrow range of the electromagnetic spectrum or very large range of the electromagnetic spectrum?
Visible light takes up only a very narrow range of the electromagnetic spectrum.
What is white light?
White light is all of the colors, ROYGBIV, combined together.
What does ROYGBIV stand for?
Red, orange, yellow, green, blue, indigo, and violet.
What is the shortest wavelength of visible spectrum? What is the longest?
Violet is the shortest wavelength and red is the longest wavelength.
What is the name for the range of all of the colors?
The visible spectrum.
What is ultraviolet light produced by?
Name 4 ways that ultraviolet light is bad for you.
1.) It gives you sunburns.
2.) It gives you wrinkles.
3.) It can cause skin cancer.
4.) It can damage you eyes.
How can you get most of these bad effects away from your body?
Wear sunscreen with a high SPF and also wear sunglasses, hats, long-sleeved shirts, and long pants.
What can UV light also travel through?
What does SPF stand for?
Sun Protection Factor.
What are some good effects of UV waves when produced by UV lamps?
It can kill bacteria on food and surgical tools.
What is a good effect on your body when exposed to little UV light?
Your skin cells produce vitamin D which allows the intestines to absorb calcium.
What would happen if you didn't have calcium?
Your teeth and bones would become very weak.
In what field are x rays useful?
In the medical field.
What happens when you have to much exposure to x rays.
It can kill or damage living cells.
What would a patient wear to keep whatever body part that doesn't need to x rayed covered?
They would wear aprons where ever appropriate.
What can x rays not pass through?
What else are x ray machines used for and what do they do?
X ray machines are used for security devices. It lets the security people see inside of bags and other containers without opening them.
What is the apron to protect the patient made out of?
Why do doctors use gamma rays?
Gamma rays are used to treat some forms of cancer and therefore doctors focus the rays on tumors inside the body to kill the cancer cells.
Why is using gamma rays to treat some forms of cancer bad?
Because it can also kill some healthy cells.
What else are gamma rays used for?
To kill harmful bacteria in food like meat and fruits.