## S5
**a)** The wavelengths need to satisfy $\frac{\lambda}{2} \cdot n= L$
**b)** $\lambda \nu = c \iff \nu = \frac{c}{\lambda}=\frac{c}{\frac{2L}{n}}$
**c)** $E = h\nu$
**d)** a not at all, b and c would be halved
**e)** By varying $L$ and observing whether the light fits into to box or not we could sweep the frequencies of the lightsource, thus creating a spectrum
## S6
**a)** The Photoelectric effect is the effect, that for light below a certain frequency cutoff no electrons can be detached from a metal, even when increasing the amplitude of the light.
It was measured by shining light with different frequencies on a metal plate, and observing when electrons are detached (and how energetic they are (. by applying a reverse voltage to slow them down))
**b)** Build a sandcastle, and expose it to waves of varying frequency. Is there a frequency so low that the castle is not destroyed, even when the amplitude is increased?
**c)** For any frequency we can find an amplitude above which the sandcastle will be destroyed
**d)** The power of a water wave to detach sand from a sandcastle is only given by it's amplitude and frequency. But because a wave is a macroscopic object there is no reason to assume the energy arrives in quantized wave particles, thus no flucto-harenaetic effect.
## S7
**a)** Particles should not interfere, but we can set up a interference experiment (double slit, single slit, etc) and see that particles do in fact interfere
**b)** Red light (long wavelength/ low frequency) is diffracted the most, thus the edge of the spot will be red'ish
**c)** $\approx 21m$. We can calculate this from the speed of sound $c_{sound}\approx 333m/s$ and $\lambda = \frac{c}{\nu}$
**d)** We have seen in b that longer wavelengths are more easily
bent around a corner. As sound has very long wavelengths and light very short ones. We can hear around corners, but not see around them.
**e)** Due to thermal fluctuations we can never truly have $v = 0$ thus the momentum is always very big (as compared to momentum of elementary particles)
**b)** Build a sandcastle, and expose it to waves of varying frequency. Is there a frequency so low that the castle is not destroyed, even when the amplitude is increased?
**c)** For any frequency we can find an amplitude above which the sandcastle will be destroyed
**d)** The power of a water wave to detach sand from a sandcastle is only given by it's amplitude and frequency. But because a wave is a macroscopic object there is no reason to assume the energy arrives in quantized wave particles, thus no flucto-harenaetic effect.
## S7
**a)** Particles should not interfere, but we can set up a interference experiment (double slit, single slit, etc) and see that particles do in fact interfere
**b)** Red light (long wavelength/ low frequency) is diffracted the most, thus the edge of the spot will be red'ish
**c)** $\approx 21m$. We can calculate this from the speed of sound $c_{sound}\approx 333m/s$ and $\lambda = \frac{c}{\nu}$
**d)** We have seen in b that longer wavelengths are more easily
bent around a corner. As sound has very long wavelengths and light very short ones. We can hear around corners, but not see around them.
**e)** Due to thermal fluctuations we can never truly have $v = 0$ thus the momentum is always very big (as compared to momentum of elementary particles)