Use the following photoelectric graph to answer the following question: what is the threshold frequency of the experimental photo-missive material? a) 9.0 e14 hz b) 5.5 e14 hz c) 2.9 e14 hz d) 0.5e 14 hz

2.9 E14 Hz

Explanation:

As we know by Einstein's equation that energy incident on the photo sensitive surface will be used by the surface to eject electron out of the surface with some kinetic energy.

This is given by

now the threshold frequency is the minimum frequency of the incident photons due to which electrons are ejected out with minimum kinetic energy or least kinetic energy.

So here when KE = 0 in the graph then corresponding to that position the frequency will be given as threshold frequency

so here from graph when KE = 0

  the unit of the measure =

explanation:

  the property that is quantified by the energy needed per of material to raise the temperature by one.

  si unit of energy = joule (j)

  si unit of temperature = kelvin (k)

  si unit of mass of material = kilogram (kg)

the property that is quantified by the energy needed per of material to raise the temperature by one is called specific heat.

the unit of specific heat is

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.