Answer:

Explanation:
Given that:
- magnetic field intensity,

- kinetic energy of electron,

- we have mass of electron,

<em>Now, form the mathematical expression of Kinetic Energy:</em>




<u>from the relation of magnetic and centripetal forces we have the radius as:</u>



<span>The longest wavelength within the visible spectrum is the red
light. The answer is letter C. It is called visible light because it is the
only light that can be seen by the human eye. Red light is the longest
wavelength around 620 to 750 nanometer. It is followed by orange which has a
wavelength of 590 t 620 nanometer. And then blue which has a wavelength of 450
to 495 nanometer. And the shortest wavelength is violet which has a wavelength
of 380 to 459 nanometer. </span>
Answer:

Explanation:
To solve the problem, the concepts related to the magnetic field and the current produced in a lightning bolt are necessary.
The current is defined by the load due to time, that is to say

Where,


So the current can be expressed as:


Once the current is found it is now possible to find the magnetic field, as this is given by the equation,

Where,
Permeability Constant
I= Current
r= radius
Replacing the values we have


I think option C is correct..hope it helps
Answer:
The atoms are aligned in a particular direction
Explanation:
The atoms become aligned in a particular direction in regions called domains, thus resulting in an overall resultant magnetism due to the spin of the electrons.