The wavelength of the light beam required to turn back all the ejected electrons is 497 nm which is option (b).
- Work function is a material property defined as the minimum amount of energy required to infinitely remove electrons from the surface of a particular solid.
- The potential difference required to support all emitted electrons is called the stopping potential which is given by
.....(1) - where
is the stopping potential and e is the charge of the electron given by
.
It is given that work function (Ф) of monochromatic light is 2.50 eV.
Einstein photoelectric equation is given by:
....(2)
where K.E(max) is the maximum kinetic energy.
Substituting (1) into (2) , we get

As we know that
....(3)
where Speed of light,
and Planck's constant , 
From equation (3) , we get

Learn about more einstein photoelectric equation here:
brainly.com/question/11683155
#SPJ4
<span>Cells with similar preferences are arranged closer together in the auditory cortex. </span>That statement presented is True. Auditory cortex is in the temporal lobe. It processes auditory information in human and as well as other invertebrates. The neurons inside the auditory cortex are organized depends on the frequency of the sound.
Since force = mass X acceleration, then the force he excerts on the earth (aka his weight) equals his mass times the force of gravity.
Therefore
W = (66 kg) X (9.8 m/ss)
W = 646.8 kgm/ss
kg m/ss are also known as Newtons, so your answer is...
646.8 N