2. Electromagnetic Waves

Question 1

Electromagnetic waves (EM) - properties

Answer 1

EM Waves:

All have the same velocity (speed)

Question 2

Radio Waves

Answer 2

Radio Waves are used to transmit RADIO & TV SIGNALS (aerial)

They can travel LONG DISTANCES

Question 3

MICROWAVES

Answer 3

Microwaves

• are used for HEATING FOOD
• ## used to COMMUNICATE with SATELLITES in SPACE

Question 4

INFRA RED WAVES

Answer 4

1. INFRA RED is emitted by ELECTRICAL HEATERS
2. IR is also used to cook food in ovens
3. IR is also used in INFRA RED CAMERAS used to check HEAT LOSS in BUILDINGS

Question 5

VISIBLE LIGHT

Answer 5

VISIBLE LIGHT

1. Used in COMMUNICATIONS by FIBRE OPTIC CABLES (very thin strands of glass). need to be FLEXIBLE
2. Transmit PULSES OF LIGHT down the fibre optic cables. This PULSES carry INFORMATION
3. Used to carry CABLE TV & TELEPHONE SIGNALS
4. VL has a SHORT WAVE LENGTH so it can carry a LOT OF INFO

Question 6

ULTRA VIOLET

Answer 6

ULTRA VIOLET

1. USE IN ENERGY EFFICIENT LIGHT BULBS
2. UV is created inside the bulb
3. Short wave length and can carry more energy than visible light
4. UV is converted to VISIBLE LIGHT
5. ADV UV uses less ENERGY than normal light bulb
6. UV also used in SUN TANNING BEDS - increases risk of skin cancer & aging of the skin

Question 7

X RAY & GAMMA RAYS

Answer 7

X RA & GAMMA RAYS used for:

1. Medical imaging
2. X rays can show BROKEN BONES
3. Gamma rays use to detect CANCER
4. Both are used because they can easily pass through BODY TISSUE

Question 8

Harmful consequence of getting a dose of X-ray radiation?

Answer 8

If you get a does of X-ray radiation it could lead to cancer