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wei1006
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Homework Statement
The following figure shows a potential divider circuit made up of a LDR and a variable resistor R. It is used to activate a buzzer circuit which sounds only at 2.6V and above. The resistance of the variable resistor varies from 100ohm to 10kohm while the resistance of the LDR varies from 110ohm to 3.6kohm.
Switch is now closed. The variable Resistor R is set at 2.4kohm and tje potential divider circuit is placed in a room with no light. Calculate the potential difference across the LDR.
Homework Equations
V=RI
Total p.d across a series circuit= add up the p.d of all components.
Total resistance across a series circuit= add up resistance of all components
Current is the same throughout the whole series circuit.
The Attempt at a Solution
I thought of ratio and proportion but I could not find the total resistance as I do not have the Total current... The final answer of this question is 3.6V.
Please help, thank you![/B]