What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is the formula used to calculate the Doppler effect: | F₀ = (fₛ x v) ➗ (v ± vₛ ) |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What is Malus's law equation | I =I₀ cos² θ |
What are progressive waves , what do they do? | Waves that move through a material (or vacuum )
A progressive wave transfers energy from one position to another |
Why are some waves called mechanical waves | if they need a substance (medium) through which to travel |
How do particles of a medium vibrate in longitudinal waves | They vibrate parallel to the direction of the wave velocity |
How do particles of a medium vibrate in transverse waves | They vibrate at right-angle to the direction of the wave velocity |
Define intensity of a wave | Rate of energy transmitted (power) per unit area at right angles to the wave velocity |
What is the formula for intensity | Power ➗ area |
Intensity is measured in... | watts per square meter (W m⁻²) |
Intensity of a wave generally decreased as it travels along. There are 2 reasons for this: | 1. Wave may 'spread out'
2. Wave may be absorbed or scattered |
As a wave spreads out, its amplitude decreases, what does this suggests? | Intensity I of a wave is related to its amplitude A |
Intensity I is directly proportional to what in symbols | I ∝ A² |
What is wave speed v , and what is it measured in | Speed with which energy is transmitted by wave
Measured in m s⁻¹ |
What is the formula used to calculate wave speed in words and in symbols | Wave speed = wavelengTH ➗ period
v = (1➗T) ✖️ wavelenght |
What is a common example of the Doppler effect? | When an emergency vehicle passes you while sounding the siren. The pitch is higher as the vehicle approaches you, and lower as it moves away |
What is the formula used to calculate the Doppler effect: | F₀ = (fₛ x v) ➗ (v ± vₛ ) |
An electric current always gives rise to a magnetic field, what is this known as? | electromagnetism |
How is a magnetic field created | by any moving charged particles such as electrons |
Light is a wave known as... | electromagnetic wave |
What is the approximate value for the speed of light in a vacuum | 3.0 x 10⁸ m s⁻¹ |
Is there a clear division between the different ranges or bands in the spectrum | No |
Wavelength in the range .....nm to .....nm in free space (vacuum) are visible to the human eye | 400nm to 700nm |
1nm = ......m | 1nm = 10⁻⁹ m |
When are X-rays produced | When electrons decelerate rapidly or when they hit a target metal at high speeds |
How are Y-rays produced | By nuclear reactions, such as radioactive decay |
What is a electromagnetic wave | a disturbance in the electric and magnetic field in space |
The electric field is shown oscillating in the ....... plane | vertical |
The magnetic field is shown oscillating in the ........ plane | Horizontal |
What is polarisation | Wave property associated with transverse waves only |
Only ........... waves can be plane polarised | Transverse |
Light is a ..... wave | transverse |
The light from the sun is unpolarised, what does this mean? | means that it has oscillating electric field in all planes at right angles to the direction in which it travels |
What is Malus's law equation | I =I₀ cos² θ |