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Why do we see a red apple as red?
Red is not in the apple. The apple reflects the red wavelength and absorbs all other wavelengths.
When electrically charged particles vibrate, they disturb the electric and magnetic fields around them. Such disturbances /waves are called ________ __________.
Electromagnetic Waves
or
EM Waves
300,000,000 m/s is also know as the ______ of _________.
speed, light
What makes some EM waves safe and some dangerous?
They have different frequencies that carry different amounts of energy.
Which wave of the EM spectrum has a wavelength greater than visible light? IR or UV ?
IR
The longest wavelenghts are seen as which color on the visible light spectrum?
Red
All electromagnetic waves are ________ in that the direction of their disturbances are perpendicular to each other.
transverse
Frequency is 23 Hz and wavelength is 16m. What is wave speed?
Wave Speed= Wavelength x frequency =
16m x 23 Hz= 368 m/s
High frequency has ____energy in EM waves
high
What are we perceiving when we see white light?
All wavelengths of light at once.
The shortest wavelengths are seen as which color on the visible spectrum?
Violet
Which EM waves has the highest frequency and energy?
Gamma Rays
Wave speed = 20m/s
Wavelength = 5 m
What is frequency?
Frequency = wave speed / wavelenght
F= 20m/s / 5m = 4 Hz
Electromagnetic Waves.
or EM Waves
The full range of wavelengths of EM waves is called the __________ __________.
Electromagnetic Spectrum
Why do we see lightning before we hear the accompanying thunder?
Light travels faster than sound.
Light waves are disturbances in _________ and _________ fields.
electric, magnetic
or
magnetic, electric
These waves move at a speed of 300,000,000 m/s in a vacuum.
EM Waves
or
Electromagnetic Waves
Which two parts of the electromagnetic spectrum are close to visible light?
Infrared Light and Ultraviolet Light
A _________ can split white light into its component colors, separating the colors by wavelength.
Prism
The destruction of ozone is caused by chemicals called as
CFCs or chloroflourocarbon
MRI makes use of _______ waves along with magnets
radio
X rays are used in medicine as it can pass through ____but not _____
muscles and organs, bones
Which of the EM waves has highest energy and can ionise living tissue
Gamma rays
Which waves can cause skin cancer when exposed to a longer duration?
UV rays