P13- Electromagnetic Waves Flashcards
What are electromagnetic waves?
What do they form?
1) Electromagnetic waves are transverse waves that transer energy from the source of the waves to an absorber.
2) Electromagnetic waves form a continuos spectrum and all types of electromagnetic wave travel at the same velocity through a vacuum or air.
Give the order of the electromagnetic spectrum.
Name some of their uses.
1) Radio Waves- television and radio
2) Microwaves- satellite communications, cooking food.
3) Infrared waves- electrical heaters, cookig food, infrared cameras.
4) Visible light (red to violet)- Fibre optic communications
5) Ultraviolet waves- Forgeries, energy sufficient lamps, sun tanning
6) X-Rays- Medical Imaging, security and treatments
7) Gamma Rays- Medical imaging and treatments
What are some dangers of radio waves?
1) There are no known dangers of radio waves.
What are some dangers of microwaves?
1) Could be dangers but there is no real proof. Heat from laptops causing infertility risks could be one.
What are some dangers of Infrared Radiation?
1) Can burn the skin/peel the skin.
What are some dangers of visible light waves?
1) They can blind you. If you were to look directly into the sun you would blind yourself.
What are some daners of ultraviolet waves?
1) Can cause skin cancer due to ionising radiation. Can also cause eye damage.
What are some dangers of X rays?
1) Can have a harmful effect on muscle tissue. Exposed to ionising radiation. Can also cause gene mutations.
What are some dangers of gamma rays?
1) They are ionising, they can cause cancer. Can also cause gene mutations.
What is the equation for wave speed?
1) Wave speed= frequency x wavelength.
Which waves can the human eye only detect?
1) They human eye can only detect visible light. The wavelength of visible light ranges from 400nm to 700nm.
What does white light contain?
1) White light contains all the colours of the visible spectrum.
When can radio waves be produced?
What happens to radio waves when they are absorbed?
1) Radio waves can be produced by oscillations in electrical circuits?
2) When radio waves are absorbed they may create an alternating current with the same frequency as the radio wave itself,. So radio waves can themselves induce oscillations in an electrical circuit
What can changes in atoms and the nuclei of atoms result in?
1) Changes in atoms and the nuclei of atoms can result in electromagnetic waves being generated or absorbed over a wide frequency range.
2) Gamma rays originate from changes in the nucleus of an atom.
