electromagneticm

Question 1

When ———– flows through a wire, what occurs ?

Answer 1

current,

A magnetic field is created around the wire
Field is made up of concentric circles perpendicular to the wire, with the wire in the centre

place compass near wire that’s carrying current . As you move the compass, it will trace the direction of the magnetic field. Changing direction of current changed direction of magnetic field.

USE RIGHT HAND RULE

Question 2

when does the strength of the magnetic field produced change ?

Answer 2

change with current and the distance from the wire.

Question 3

The ———– the current through the wire, or the —— to the wire you are, the ———- the field is

Answer 3

larger, closer, stronger

Question 4

How to increase strength of magnetic field that a wire produces

Answer 4

wrap wire into coil = solenoid
This happens because field lines around each loop of wire line up with each other, this results in lots of field lines pointing in the same direction that are very close to each other .

closer field lines = stronger field

Question 5

The magnetic field inside a solenoid is strong and …

Answer 5

uniform
Outside the coil, the magnetic field is just like the one round a bar magnet = means end of solenoid act like north and south pole of a bar magnet.
You can work out which is the south pole and which is north pole using right hand role

Question 6

how to increase solenoid magnetic field

Answer 6

increase the current flowing through the coil, increase the number of turns in the coil, and add a ferromagnetic core (like iron) inside the solenoid

Question 7

The iron core becomes an ———- magnet whenever current is flowing.
If you stop current, what will happen ?

Answer 7

magnetic field disappears
A solenoid with a magnetic field is called a electromagnet