Producing electromagnetic waves

Question 1

with a magnet which has both south and north poles and a coil around the north pole what happens when moving the coil in a magnetic field?

Answer 1

produces a current.

Question 2

with an iron nail with a coil wrapped round it what happens when the current flows?

Answer 2

coil and nail are magnitised.

Question 3

radio waves: what happens when electrons in an aerial move and what does this result in? what does this inetraction between alternating magnetic and electric fields enables?

Answer 3

produces a change in the magnetic field next to it.
produces a change in electric field which in turn changes the magnetic field again.
radio waves moves through space without the need for particles.

Question 4

radio waves: what happens when the em waves reach an aerial?

Answer 4

electrons move into aerial at same frequency as radio wave.

Question 5

visible light: how are the elctrons arranged?

Answer 5

shells at different distances from the nucleus.

Question 6

visible light: what do the shells corrospond to?

Answer 6

different energy levels.

Question 7

visible light:why might the electron arrangment change?

Answer 7

• absorption of electromagnetic radiation.
• electron moving further from the nucleus; a higher energy level.
• emission of electromagnetic radiation. (electron moves closer to the nucleus; a lower energy level.)

Question 8

gamma rays: where are they emitted from and what do they do to become mofe stable?

Answer 8

nucleus of an atom when the protons and neutrons rearrange themselves to become more stable.

Question 9

gamma rays: why do they have a short wavelength?

Answer 9

large changes in energy.