Can a reed switch use a wheatstone bridge/potential divider?

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SUMMARY

The discussion centers on the operation of reed switches and Light Dependent Resistors (LDRs) within Wheatstone bridge and potential divider configurations. It is established that reed switches operate through magnetic actuation, making them unsuitable for direct integration into Wheatstone bridge circuits, which typically utilize resistive elements. The LDR, however, can effectively function within these arrangements, where its resistance varies with light intensity, influencing voltage output. The conversation also explores hypothetical scenarios involving the interaction of reed switches and LDRs in circuit configurations.

PREREQUISITES
  • Understanding of reed switch operation and magnetic actuation
  • Knowledge of Light Dependent Resistors (LDR) and their behavior under varying light conditions
  • Familiarity with Wheatstone bridge circuit principles
  • Basic concepts of potential dividers and voltage output calculations
NEXT STEPS
  • Research the integration of LDRs in Wheatstone bridge circuits for light sensing applications
  • Explore the principles of potential dividers and their applications in electronic circuits
  • Investigate the effects of varying resistance in Wheatstone bridges using different sensor types
  • Examine the use of reed switches in control circuits and their limitations
USEFUL FOR

Electronics students, hobbyists, and engineers interested in sensor applications, circuit design, and the integration of magnetic and resistive components in electronic systems.

Daniel2244
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Homework Statement


Describe the principle of operation of reed switch and LDR using wheatstone bridge and potential divider arrangement

I can't find any website that says a reed switch uses a wheatstone bridge or potential divider arrangement. The only find I have found it that that a magnet if used to close and open the switch. When a magnet is moved towards the open reed switch it causes the reed pins to move together completeing the circuit. And when a magnet is applied to a closed reed switch it causes the reed pins to repel causing them to open breaking the circuit.
Because they work using a magnet I wouldn't think they would be used in a wheatstone bridge and potential divider arrangement because they are manly used for resistance devices. For example, strain gauge and LDR.

Homework Equations

The Attempt at a Solution


I understand how a LDR is used in a potential divider arrangement:
When the resistance of the LDR is small (When light intensity on LDR is very high),there is a small voltage drop across the LDR; this means that the output voltage (Vout) from the voltage divider is small and the transistor is switched off.
In the dark the large resistance of the LDR takes a large share of the voltage supply so Vout is large and the transistor and LED both switch on.

And in a Wheatstone bridge circuit:
In a Wheatstone bridge circuit an a resistor is replaced (normally labelled Rx) with a LDR. As light changes it causes the resistance of the LDR to change which produces a voltage across the bridge of the circuit
 
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It would help if we knew the grade or context of the question.

What would happen if you wound a long thin wire around the reed switch, then connected that coil across the wheatstone bridge in place of the galvanometer?

What could you do if the reed switch controlled a light source that illuminated an LDR in different positions in the bridge circuit?
 

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