Chapter 13 - Physics Flashcards
Where do electromagnetic waves transfer energy from?
A source to an absorber
What is the electromagnetic spectrum made up of?
Radio waves Microwaves Infrared radiation Visible light (red to violet) X-Rays and gamma rays
What can the human eye only detect?
It can only detect visible light, wavelength of visible light ranges from just below 400nm to above 700nm
What does white line contain?
It contains all the colours of the visible spectrum
What is infrared radiation used for?
It is used for carrying signals from remote control handsets and inside optical fibres
What are microwaves used for?
To carry satellite TV programmes and mobile phone calls.
What are radio waves of different frequencies used for?
Different purposes because the wavelength of waves affects: how far they can travel, how much they spread and how much information they can carry.
Where are X-rays used?
In the hospitals to make X-ray images.
What are gamma rays used for?
To kill harmful bacteria in food, to sterilise surgical equipment, and to kill cancer cells.
Why are X-rays used in hospitals?
To make images of your internal body parts and to destroy tumours at or near the body surface.
