As per the question the mass of the boy is 50 kg.
The boy sits on a chair.
We are asked to calculate the force exerted by the boy on the chair at sea level.
The force exerted by boy on the chair while sitting on it is nothing else except the force of gravity of earth i.e the weight of the body .The direction of that force is vertically downward.
At sea level the acceleration due to gravity g = 9.8 m/s^2
Hence the weight of the boy [m is the mass of the body]
we have m = 50 kg.
Hence w = 50 kg ×9.8 m/s^2
=490 N kg m/s^2
= 490 N
Here newton [N] is the unit of force.
An intersystem crossing (ISC) is a non-radiative process that involves the transition between two electronic states with different spin multiplicity. That is, when an electron is excited in a molecule in a basal singlet state (either by absorption or radiation) into a state of greater energy, an excited singlet or triplet state can be obtained.
Therefore, ISC is understood as an a non radio active transition between states with different spin multiplicity.
Correct answer is C: a radiative transition between states with the same spin.
To solve this problem we will apply the concept of current defined as the electron charge flow by the number of electrons per second. That is,
I = q*N
Here q is Flow of electric charge in one second and N the number of electron flow per second.
A the same time the power is described as the applied voltage for the current.
P = VI
We know the charge of electron, Coulombs, then the current is
And the power in the Beam is