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What belongs in each mystery box?

Every mystery box holds the same value. Make the two sides balance.

4 × ? + 545Equal values make a level balance.

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ScienceAges 13-15Physics (O Level): Electricity & magnetism
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Potential divider circuits

In a potential divider circuit connected to a 70 V DC supply, resistor R₁ = 27 Ω and resistor R₂ = 63 Ω are connected in series. Using V_out = (R₂ ÷ (R₁ + R₂)) × V_in, calculate the potential difference across R₂.

Apply the potential divider equation V_out = (R₂ ÷ (R₁ + R₂)) × V_in across two series resistors connected to a DC source.

+−R
V_in = 70 V · R₁ = 27 Ω, R₂ = 63 Ω · V_out = [R₂ ÷ (R₁ + R₂)] × V_in
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