magnetic fields and EM induction

Question 1

define magnetic flux density

Answer 1

the force per unit length per unit current on a current carrying conductor at right angles to magnetic field lines

Question 2

define the Tesla

Answer 2

the magnetic flux density that caused a force of 1N on a wire of length 1m with 1A of current flowing through it.

Question 3

what is Fleming’s left hand rule?

Answer 3

used to work out the direction of the force exerted on a wire based off of the directions of the current and magnetic field.
force is perpendicular to current, which are both perpendicular to the direction of the magnetic field.

Question 4

what must you rememeber to take into account when working out the direction of the force on an electron/electron carrying wire in a magnetic field

Answer 4

current = direction a positive charge would move
so must reverse the actual direction of the flow of electrons, as electrons are negative.

Question 5

briefly describe an experiment to verify the equation F=BIl

Answer 5

run a metal wire attached to a circuit (with a variable current) through a pair of magnets on top of a top pan balance

from N3L - the force on the wire (due to the magnetic field) is equal and opposite to the force on the magnet (which produces a reading on the scales)

vary the current ,work out the force the wire from the mass displayed on the balance

plot and analyse a graph.