Amole of yellow photons of wavelength 527 nm has kj of energy.

Explanation:

It is known that relation between energy and wavelength is as follows.

            E =

where,    h = plank's constant =

              c = speed of light =

          = wavelength

Convert nm into m as follows.

                       = m

Therefore, calculate the energy as follows.

                 E =

                    =

                    = J

Hence, energy of the yellow light is J.

Now, calculate the moles of yellow light as follows.

               = J

               = 227144 J

or,           = 227.14 kJ        (as 1 kJ = 1000 J)

Thus, we can conclude that a mole of yellow photons of wavelength 527 nm has 227.14 kJ of energy.

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.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia