Answer:
Objects between the source and observer produce possible shadows known as the umbra and the penumbra.
The umbra is a totally shadowed area, no light travels directly from the source to the observer.
The penumbra is a partially shadowed are where some of the source light travels directly to the observer an some of the source light is blocked from the observer (the object blocking the light is not a point object).
The question apparently refers to the differences seen by the observers.
<u>electrial</u><u> </u>
<u> </u><u>In an electrical circuit, electric current flows through the closed path</u>
<u>magnetic</u><u> </u><u>circuit</u><u> </u>
<u>In the magnetic circuit, magnetic flux flows through the closed path</u>
It could be warmer solid, or liquid, or gas, depending on the pressure and the amount of heat added.
