14
MICROWAVING PRINCIPLES
Microwave energy has been used in this country to cook and reheat food since early
experiments with RADAR in World War ll. Microwaves are present in the atmosphere
all the time, both naturally and manmade sources. Manmade sources include radar,
radio, television, telecommunication links and car phones.
Microwave oven is a Group 2 ISM equipment in which radio frequency energy is
intentionally generated and used in the form of electromagnetic radiation for the
treatment of material. This oven is a Class B equipment suitable for use in domestic
establishments and in establishments directly connected to a low voltage power
supply network which supplies buildings used for domestic purposes.
CONVERSION CHARTS
HOW MICROWAVES COOK FOOD
The microwaves cause the water molecules to vibrate which causes FRICTION, i.e.
HEAT. This heat then cooks the food. Microwaves are also attracted to fat and sugar
particles, and foods high in these will cook more quickly. Microwaves can only
penetrate to a depth of
4-5cm and as heat spreads through the food by conduction, just as in a traditional
oven, the food cooks from the outside inwards.
In a microwave oven, electricity is converted into
microwave by the MAGNETRON.
The microwaves bounce off the metal walls and the
metal door screen.
Then they pass through the cooking containers to
be absorbed by the water molecules in the food, all
foods contain water to a more or lesser extent.
Oven Cavity
Magnetron
Waveguide
Turntable
REFLECTION
TRANSMISSION
ABSORPTION
Microwave
Water Molecule Absorption
Vibration
WEIGHT MEASURES
15 g
½ oz.
25 g
1 oz.
50 g
2 oz.
100 g
4 oz.
175 g
6 oz.
225 g
8 oz.
450 g
1 g.
FLUID MEASUREMENTS
1 Cup
= 8 fl.oz.
= 240 ml
1 Pint
= 16 fl.oz. (UK 20 fl.oz.)
= 480 ml (UK 560 ml)
1 Quart
= 32 fl.oz. (UK 40 fl.oz.)
= 960 ml (UK 1120 ml)
1 Gallon
= 128 fl.oz. (UK 160 fl.oz.)
= 3840 ml (UK 4500 ml)
VOLUME MEASURES
30 ml
1 fl.oz.
100 ml
3 fl.oz.
150 ml 5 fl.oz. (¼ pt)
300 ml
10 fl.oz.
(½ pt)
600 ml 20 fl.oz. (1pt)
SPOON MEASURES
1.25 ml
¼ tsp
2.5 ml
½ tsp
5 ml
1 tsp
15 ml
1 tbsp
Desuk_KOR6M17(영)_A5.indd 14
16. 9. 9. 오후 1:34