magnetic fields

Yes

BIl

B - magnetic flux density

I - current in the wire

L - length of the wire

Thumb - force

First finger - field

Second finger - current

Flux density measured in Tesla(T) or Webers/meters^2(Wb/m^2), flux per metre^2

The amount of magnetic flux in an area taken perpendicular to the magnetic flux’s direction

Perpendicular

F=BQv

Perpendicular to its motion, causing it to move in a circular motion

Electric and magnetic

A cyclotron is made up of 2 semicircular electrodes called ‘Dees’ with a magnetic field applied perpendicular to the Dees and an alternating potential difference applied between the Dees

Each Dee is a metal electrodes with opposite charges, this creates an electric field in the gap between the two Dees. This is what accelerates the particles.

The magnetic field causes the particles to move in a circular motion, which allows it to gain speed whilst minimising space. As they speed up the radius of their motion increases, until it breaks free tangential to one of the Dees.

The induced emf is directly proportional to the rate of change of magnetic flux linkage

The direction of the induced emf is such as to oppose the change that induces it

The electrons experience a force pushing them to one end of the conductor creating an emf across the conductor

The rod bey faraday’s law, it is changing flux as it moves through the field hence an emf is induced

Oscilloscopes are used to displace AC waves, the x axis is called the time base and shows how long it takes the wave to move 1 division and the y axis shows how much PD is needed to move tye wave up 1 division,

Using this we find the peak voltage, time period and frequency

It is a measurement of the total magnetic field lines that passes through a given area measured in Wb

A primary coil wrapped around an iron core with an alternating potential difference creates an alternating magnetic field, this magnetic field induces an emf in a secondary coil also wrapped around the core, this makes a I in the secondary coil

Alternating current

An emf is induced by a changing magnetic field and so the emf induced is alternating producing an alternating current

By changing the number of coils, the transformers can be used to increase the voltage and reduce current when transporting power with minimal energy loses

The voltage is then dropped again locally to ensure safe usage in households

Ns/Np = Vs/Vp

The ratio of output power in the transformer to input power

IsVs/IpVp

Secondary

Step-up transformers increase voltage so more coils need to be in secondary coil for larger p.d.

As the primary coils magnetic field induces emf in the secondary coil, it also induces emf hence the mini currents in the iron core

By lenz’s law the emf created snd its field opposes that of the primary coil. Causes energy loss via resistive heating of the iron core by the eddy current - reducing efficiency

A laminated core

Thin sheets of iron with an electrical insulator between, reducing the eddy current

Distance from the equilibrium to the highest/ lowest point

Distance from the minimum point to the maximum point

The average of all the squares of the possible voltages

Gives the average value of voltage output of the supply

Irms = I0/root two

Vrms = V0/root two

Product of flux and number of turns

The total amount of magnetic field lines passing through a number if loops

Wb

Flux leakage - magnetic field does not follow the intended oath fully

Heating in iron core and copper wires

Force acts inward

Velocity is tangential to object

Work is not done so no change in ke so no change in speed

R = mv/Bq

The output voltage remains the same as if it was completely efficient current is altered

Motion of charged particles or permanent magnet made of a magnetic material like iron

X into

O out of

Long coil of wire with a large number of loops

The closer to the source of the field

T the measure of the strength of the magnetic field , B

Use right hand

makes it experience a force

Induces a flow of current using relative motion between conductor and magnetic field

increase speed of conductors movement relative to the magnet And vice versa

Increase the loops in the conductive wire

Anode supplied with a high voltage - thermionic emission

There is relative movement between the magnetic field and the conductor

Corresponds to the conductor cutting through the lines of flux so there is a change in magnetic flux linkage through the conductor - farradays law

Varying the area of the conductor

Reduce time base setting as uncertainty due to the size of time base setting so will stretch it out more

Induced current as such to appose the change inducing it , lenz’s law

Switch on current increases flux in y

Current in opposite direction to oppose the flux

Switch off, flux in y due to x decreases so current travels in the opposite direction to previous to oppose the change

The direction of force acting on a mass places there