PHYSICS - Electromagnetic spectrum

What is the electromagnetic spectrum?

a family of waves

What does each part of the spectrum have thats different

different properties

what is the strongest wave on the spectrum

gamma rays

what is the weakest wave on the spectrum

radiowaves

What is the first common property of waves in the spectrum

All parts travel at the same speed (of light)

What is the speed of light

3×10*8 m/s

What is the second common property

all parts of the spectrum can travel through space

what is the third common property

all parts of the spectrum are transverse waves

Name two things that gamma rays (high frequency) can be used for

sterilising surgical equipment, killing harmful bacteria in food

Name two things that xrays (lower frequency than gamma) can be used for

producing pictures of bones to check for damage, in industry to check metal components for cracks

Name two properties of visible waves

made up of 7 different colours, only rays visible to the human eye

Name two things that infared rays are used for

remote controls, communication

Name two things that microwaves are used for

communication, cooking

What are two things that radio waves aree used for

radio, tv

How can xrays see bones

the rays can pass through the skin tissue easily

What do xrays and gamma rays have in common

they are ionising

what can ionising rays do

damage the DNA in cells

what can low does of xrays and gamma rays cause

cancer

what may kill cancer cells

high does of xrays and gamma rays

how are xrays made

slowing electrons down very quickly

how are xrays given off

by firing a beam of fast moving electrons into a metal plate, stopping the electrons rapidly and giving off xrays

what material can absorb some of gamma ray energy

lead

what is the wavelength like in gamma rays

short

where are high energy electromagnetic waves emmitted from

the nucleus

where is there an overlap in frequency between xrays and gamma rays

lower freq. of gamma rays and higher freq. of xrays

give two uses of gamma rays

treating cancer radiotherapy

how do microwaves heat up food

by heating water molecules inside food