ELECTRICITY & ELECTRONICS INT 2 PHYSICS ELECTRICITY & ELECTRONICS

LOCKERBIE ACADEMY PHYSICS DEPT Ways to work out voltage divider circuits. Follow the plan below:

LOCKERBIE ACADEMY PHYSICS DEPT 1. Identify the component 2. Set the conditions 3. Decide what happens to the resistance Work out the effect of the voltage across the component 5. Find the effect on Vout

LOCKERBIE ACADEMY PHYSICS DEPT V Vs 0V

V Vs 0V 1. Identify the component LDR

V Vs 0V 2. Set the conditions As light increases

As light increases RESISTANCE decreases V Vs 0V 3. Decide what happens to the resistance As light increases RESISTANCE decreases

As resistance decreases voltage across the LDR decreases Vs 0V Work out the effect of the voltage across the component As resistance decreases voltage across the LDR decreases

As VLDR decreases Vout increases as they are not the same Vs 0V 5. Find the effect on Vout As VLDR decreases Vout increases as they are not the same

1. Identify the component V Vs 0V 1. Identify the component 2. Set the conditions 3. Decide what happens to the resistance Work out the effect of the voltage across the component 5. Find the effect on Vout

As light increases RESISTANCE decreases How this circuit works LDR V Vs 0V As light increases RESISTANCE decreases Voltage across the LDR decreases As VLDR decrease Vout increases as they are not the same SUMMARY: As light increases Vout increases USE: Greenhouse sprinkler system Heating to come on during the day

Now try this one yourself Vs 0V V t

LOCKERBIE ACADEMY PHYSICS DEPT Thank you for your patience