Physics- Waves

What do waves carry from one place to another?

What is the wavelength of a wave?

What is the frequency of a wave?

What is the amplitude of a wave?

The formula for frequency is 1/time period

What is the wave equation?

The direction of vibration for transverse waves is [blank_start]perpendicular[blank_end] to the direction of travel where as for longitudinal waves it is [blank_start]parallel[blank_end] to the direction travel

The phase is [blank_start]a specific point on a wave[blank_end]

The phase angle can also be written as fractions of wavelengths, degrees or radians; 360 degrees = [blank_start]1[blank_end] wavelength = [blank_start]2n[blank_end] radians 180 degrees = [blank_start]1/2[blank_end] wavelength = [blank_start]1n[blank_end] radians 90 degrees = [blank_start]1/4[blank_end] wavelength = [blank_start]1/2n[blank_end] radians 270 degrees = [blank_start]3/4[blank_end] wavelengths = [blank_start]3/2[blank_end] radians

How to standing waves form? A wave is [blank_start]reflected[blank_end] and [blank_start]superposition occurs[blank_end], [blank_start]producing nodes and antinodes[blank_end]

A node is [blank_start]an area of no displacement[blank_end]

An antinode is [blank_start]an area of maximum displacement[blank_end]

What is the distance between the nodes for a standing waves?

Diffraction is [blank_start]the spreading out of waves[blank_end] [blank_start]around an obstacle or through a gap[blank_end]

What does s diffraction pattern of laser light passing through a slit look like?

What happens to the size and brightness of the spots if you use a smaller diffraction grating?

When the wave displacements add to make a larger displacement we call it [blank_start]constructive interference[blank_end]. When they add and cancel out to make zero displacement we call it [blank_start]destructive interference[blank_end].

The phase difference when 2 waves are exactly in step is [blank_start]2n pi[blank_end] and the path difference is [blank_start]n[blank_end] wavelengths When in antiphase the phase difference is [blank_start](2n+1) pi[blank_end] and the path difference is [blank_start](2n+1)wavelengths/2[blank_end]

Sources of waves are said to be coherent when they have [blank_start]the same frequency[blank_end], [blank_start]a constant phase relationship[blank_end] and [blank_start]a similar amplitude[blank_end]

Path difference is [blank_start]the difference in distance traveled[blank_end] by 2 waves arriving [blank_start]at a point from the source[blank_end]

What is the refractive index?

The formula for Snell's Law is [blank_start]n1sin1=n2sin2[blank_end]

The critical angle is [blank_start]the angle at which the light[blank_end] exits [blank_start]parallel to the boundary[blank_end], greater than this causes [blank_start]total internal reflection[blank_end]

Polarisation is when [blank_start]all the oscillations[blank_end] occur [blank_start]in one single plane[blank_end]

The electrons are emitted instantaneously because [blank_start]the photon[blank_end] has energy greater [blank_start]than or equal to the work function[blank_end] where as if it were a wave then [blank_start]the energy would have to build up[blank_end] to the work function so there would be [blank_start]a delay[blank_end]

The wave theory cannot explain the photoelectric effect in terms of frequency because [blank_start]low frequencies never emit electrons[blank_end], therefore there must be [blank_start]a minimum frequency[blank_end]

The work function is [blank_start]the minimum amount of energy[blank_end] an electron needs in [blank_start]order to escape the surface of the metal[blank_end]

The equation for photon energy is; Photon Energy = [blank_start]Planck's constant x Frequency[blank_end]

The equation for kinetic energy is; KE = [blank_start]hf - work function[blank_end]

1eV = [blank_start]1.6 x 10^-19[blank_end]

Planck's constant = [blank_start]6.63 x 10^-34[blank_end]