infrared

Question 1

what is infrared radiation given out by

Answer 1

all hot objects

Question 2

the hotter the object …

Answer 2

the more IR radiation it gives out

Question 3

how is IR radiation used in thermal imaging

Answer 3

camera detects the IR radiation and turns it into an electrical signal which is displayed
different colours represent different amounts of IR radiation being detected
used by police to find suspects trying to escape in the dark

Question 4

how do infrared sensors work

Answer 4

a change in IR radiation sounds an alarm or turns on a security light

Question 5

how do infrared sensors used

Answer 5

a change in IR radiation sounds an alarm or turns on an security light

Question 6

how does IR radiation cause food to cook

Answer 6

temperature increases when an object absorbs IR radiation

Question 7

how do electrical heaters work

Answer 7

long piece of wire heats up and emits lots of IR radiation
the emitted radiation is absorbed by objects in the room and the air in the room (energy is transferred by IR waves to thermal energy stored of the objects) so their temps increase

Question 8

how does infrared radiation work on phones or laptops or TV remotes

Answer 8

IR radiation use to transfer information when distance is small and in line of sight of the emitter

Question 9

what are optical fibres

Answer 9

thin glass or plastic fibres that carry data over long distances as pulses of IR radiation using total internal reflection

Question 10

what is the danger of IR radiation

Answer 10

can cause skin burns