Question 2 (10%)
An electromagnet of flux equal to 5Wb increases uniformly to 20Wb in a period of 2s Calculate the
Voltage induced in a coil having(6 turys and is stationary in the magnetic field.
(10%)

45 V

Explanation:

Electromagnetic induction occurs when there an electromotive force is induced in a coil due to a change in magnetic flux through the coil.

Mathematically, the induced voltage is given by Faraday-Newmann-Lenz law:

where

N is the number of turns in the coil

is the change in magnetic flux

is the time elapsed

In this problem,

N = 6 is the number of turns in the coil

The change in magnetic flux is:

is the time elapsed

Substituting, we find the induced voltage:

And the negative sign only indicates the direction.

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

in this image, you can see solar radiation going through ocean water.

no image, but probably absorption