A2 practical design help?

Question

I'm prepping for my A2 Physics practical to be held in 4 days' time. I was wondering what's the simplest way to draw effective arrangements of:

(i) a hall probe (e.g. do i just draw two wires protruding from a cylinder shape - probe - connected in series to a 'datalogger' and in parallel to a power supply? or are more wires needed?)

(ii) double light gates (how many wires do i need? where do they go?)

(iii) Geiger-Muller tube (how many wires needed and what to use to determine count rate)

(iv) platinum resistance thermometer and thermocouple thermometer (how would i draw the shapes of them? are they attached to probes? what are they connected to?)

help with any of the above will be much appreciated!

[So it's like

(T)----------------------[Datalogger]
| (V) |
--------------------

?

If the two wires only connect from the probe to the voltmeter it would be in series, no?]

Current source as in a power supply?

Answer 1

(i) A Hall probe? do you mean a Hall-Effect probe for measuring magnetic fields? If so, that has four wires: two connected to a current source, and two to a voltmeter.

(iii) The Geiger-Muller tube has two wires; voltage pulses are developed across a load resistor, and a digital counter is used to measure total counts, and a frequency meter to measure count rate. See http://en.wikipedia.org/wiki/Geiger_tube

(iv) Both platinum resistance and thermocouple thermometer are connected with two wires to the probe. The resistance probe would be represented by a resistor symbol (zig-zag line), sometimes in a circle with a "T" next to it. The two wires would be connected to a voltage source and ammeter. The thermocouple is represented by an upside-down "V", also inside a circle with a "T". The wires go to a sensitive voltmeter, no power source needed.

Answer 2

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