Work function for platinum is 6.35 eV. (a) Convert the value of the work function from electron volts to joules. J (b) Find the cutoff frequency for platinum. Hz (c) What maximum wavelength of light incident on platinum releases photoelectrons from the platinum's surface? nm (d) If light of energy 7.38 eV is incident on platinum, what is the maximum kinetic energy of the ejected photoelectrons? Give the answer in electron volts. eV (e) For photons of energy 7.38 eV, what stopping potential would be required to arrest the current of photoelectrons? V

i don't understand is there any other way you can rephrase it plz let me know in the comments and i will do it.

explanation:

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.

magnets not strong enough

explanation: