• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Investigation of determination of flux density of magnets(plane)

Extracts from this document...

Introduction

Investigation of determination of flux density of magnets

Introduction

A magnet is a material or object that produces a magnetic field. A low-tech means to detect a magnetic field is to scatter iron filings and observe their pattern, as in the accompanying figure. A ‘hard’ or ‘permanent’ magnet is one that stays magnetized, such as a magnet used to hold notes on a refrigerator door. Permanent magnets occur naturally in some rocks, particularly lodestone, but are now more commonly manufactured. A ‘soft’ or ‘impermanent’ magnet is one that loses its memory of previous magnetizations. ‘soft’ magnetic materials are often used in electromagnets to enhance the magnetic field of a wire that carries an electrical current and is wrapped around the magnet; the field of the ‘soft’ magnet increases with the current.

As current flows through a wire, the wire is magnetized and it generates a magnetic field around it, and this magnetic field will interact with any other magnetic field to produce a magnetic force. We can predict the direction of force by using Fleming’s left-hand rule. There are three

...read more.

Middle

The size of the magnetic force depends on:

The magnetic field strength, B

The current I, flowing at right angles to the field

The length l of the conductor I the magnetic field. ( in this case, the length of the conductor will be the length of the magnet)

Sum up these three factor, we can get an equation for the force:

F = BIl

We can see from this equation that the force F, is proportional to each of these quantities.

we can arrange the formula:

B = F/Il

A magnetic field has a strength of one tesla ( 1T ) , if it exerts a force of 1N on a conductor of length 1m, carrying a current of 1A at right angles to the field. Thus the equation b = F/Il defines the quantity magnetic field strength( flux density) B, and its unit, the tesla: 1T = 1NA-1m-1

As the force of magnetic is equal to the restoring weight, the length of the conductor can be measured by measuring the length of magnet, and the current can be measured by an ammeter. Therefore the magnetic flux density can be calculated easily.

There are few factors which I think would affect my experiment:

...read more.

Conclusion

An electronic balance

As it is electronic, and it will give the value up to 2 decimal places, so that produce more accurate results.

Copper wires

Variable resistor

This is used to vary the resistance in the circuit to give different current.

An ammeter

This is used to measure the amount of current

Safety

Wearing goggles

Watching out the current, if it gets to large, the wire could be burnt or get to hot. Make sure do not touch the wire if it gets too hot.

Method

  1. set up equipments like the diagram
  1. switch on the power supply and vary the variable resistance, record the current shown on the ammeter and adding paper pieces on to the frame
  1. as soon as the current balance goes to equilibrium which can be seen by comparing the level of two frame on each side, to see if they are at the same level, and switch of the power supply
  1. carefully moving the stored paper on to the balance and record the mass shown on the screen
  1. changing different current by varying the variable resistor and do the same steps as above
  1. repeat the experiment with the same current
  1. calculate the average mass of paper for each current and use the average to plot a weight—current graph
  1. tidy up the equipments

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Fields & Forces section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Fields & Forces essays

  1. Peer reviewed

    Investigating the forces acting on a trolley on a ramp

    5 star(s)

    Another factor which contributes to the uncertainty associated with light gate is the position of the emitter and receiver within the LED and furthermore, the position of the LED. The distance measured from the starting point and where the beam actually is in the light gate could differ by a few millimetres.

  2. Peer reviewed

    paper cones investigation

    5 star(s)

    5.19 6 200 3.27 4.12 -21 167 3.43 3.41 1 143 2.79 2.90 -4 125 2.72 2.52 8 111 2.21 2.22 -1 100 1.64 1.98 -17 90.9 2.01 1.79 12 83.3 1.58 1.63 -3 76.9 1.84 1.49 23 71.4 1.37 1.37 0 66.7 1.35 1.27 6 62.5 1.16 1.18 -2

  1. Investigating a factor affecting the voltage output of a transformer.

    This is because as the primary voltage is increased, so the alternating current in the primary coil also increases. This creates an alternating magnetic field in the primary coil, resulting in the magnetic field lines changing direction more frequently. They are cut more times in a given time period by

  2. Maglev Trains And The Technology Behind Them (magnetism)

    A phenomenon know as the Meisner effect is exploited where superconductors are used to levitate magnets above. The track is either an aluminium guideway or a set of conductive coils. The magnetic field of the superconducting magnets aboard the maglev vehicle induces an eddy current in the guideway.

  1. What Affects the Strength of Magnetism Exerted By an Electromagnet?

    The size of the magnetic field produced should be proportional to the charge of the particle. Bigger charges should produce bigger fields. However, the speed at which the charge is moving should also affect the field strength. The faster the particle vibrates, the more energy it has.

  2. To investigate the effect of current on the strength of an electromagnet field.

    If sand was poured into the plastic cup too fast it would unbalance the cup and therefore fall. Also if the sand was not poured in evenly in the beaker it would build up on one side of the cup and unbalance it.

  1. Aurora- Light of Mystery.

    The earth and its magnetic field lie within this magnetic cocoon which protects us from the solar wind. This happens because when a charged particle travels across magnetic fields a force is created and will deflect the particle around the earth.

  2. Investigating Electromagnets

    Investigating the affect of number of coils is feasible because the power pack does not reset and this variable could be easily measured through counting. What I will investigate: The variable that I will investigate will be the number of coils for the above reasons found in preliminary work.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work