Chapter 13: Electromagnetic Spectrum Flashcards
Master definitions
Define
Electromagnetic waves
Hint: in the name
Group of waves that consists of magnetic and electric field wave. Different wavelengths of electromag waves form the electromagnetic spectrum
List
electromagnetic spectrum from highest freq to lowest
Low freq= long wavelength, high freq= short wavelength
Gamma ray(>10^18), Xray(10^16-18), Ultraviolet ray(10^14-16), Visible light(10^14), Infrared radiation(10^12-14), Microwaves(10^9-12), Radiowaves(<10^9)
Low freq= long wavelength, long freq= short wavelength
Grandma X usually likes Indian Muslim Rojak
MCQ
Properties of electromagnetic waves
v = λ f!
- Transverse or longitudinal, 2. Can Travel in vacuum?
Transverse, yes
Speed of electromagnetic waves
What is the speed of waves dependent on
v = λ f!
3x10^8 m/s
dependent on medium
List
Uses of Radiowaves
List
-
Radio Astronomy
* involves detecting and studying RW’s produced by planets & stars -
Radio Frequency Identification Tags (RFID tags)
* contains small thin circuit. Reader device sends radio wave to tag, tag transmits back data to reader (commonly used to tag library books, etc.) -
Television & communication purposes
* Longer wavelength radio waves are used as they can better travel ard obstacles like mountains
RW= radio waves
List
Uses of microwaves
- Microwave Ovens
-
Carries signals to and from satellites for satellite television, GPS, and phone communication
* able to penetrate atmosphere, travel through haze, snow, light rain, cloud and smoke
List
Uses of Infrared Radiation
- Intruder alarms
- Infrared cameras
- Remote controllers
List
Visible Light
- allows us to see
- Used in optical fibres
- Photography
List
UV radiation
- Sunbeds for artificial tanning
- Sterilisation of equipment and water(e.g. NEWater is disinfected using UV )
- Bank note authentication(authentic bank notes have pigments that glow under UV light)
LIst
X-ray
- Used in chemotherapy
- Used for imaging for making medical diagnosis
- Used for imaging or security checks
- Industrial defect detection
List
Gamma rays
- Targeted radiation therapy
- Sterilising food
Types of Ionising radiation
2 types
- Electromagnetic radiation 2. Nuclear radiation
Define
Ionising radiation
higher frequency forms of radiation that has sufficient energy to cause ionisation of medium through which it pass
ionisation- knock out an electronm from a particular atom or molecule
able to penetrate deep into the body making them extremely harmful
name
effect of ionising radiation on living cells
- death of living cells
- mutation of living cells, leading to organ failure and diseases
- heating up of living cells
name
types of electromag waves that are ionising radiation
- Gamma rays
- X-rays
- Ultraviolet rays