A solenoid has an internal magnetic field of 0.28T. What is the energy density of the field?

Energy density,

Explanation:

It is given that,

Magnetic field in a solenoid is 0.28 T

We need to find the energy density of the field. The energy density of the magnetic field is given by below formula as follows :

So, the energy density of this field is .

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.