Question

Describe, using the relevant physics, how moving a magnet near a [ 1 2 ] solenoid induces a voltage across it. How does the speed of the magnet a ect the voltage? What about turning the magnet upside down?

Answer 1

Answer:

Explanation:

Moving a magnet might cause a change in the magnetic field going through the solenoid. Whether or not it will change depends on the movement.

According to Faraday's law of induction a voltage is induced in a coil by a change in the magnetic flux. Magnetic flux is defined as the dot product of the magnetic field (a vector field) by the area enclosed by a loop of the coil.

$\Phi B = -\int{B} \, dA$

The voltage is induced by the variation of the magnetic flux:

$\epsilon = -N * \frac{d \Phi B}{dt}$

Where

ε: electromotive fore

N: number of turns in the coil

ΦB: magnetic flux

Moving the magnet faster would increase the rare of change of the magnetic flux, resulting in higher induced voltage.

Turning the magnet upside down would invert the direction of the magnetic field, reversing the voltage induced.