Formula list for D.c Circuits
* This calculator is a quick reference, they might have some errors.
Ohm's Law
Voltage (V): | ? Enter voltage in Volts(V) |
Resistance (R): | ? Enter resistance in Ohms(Ω) |
Current (I): |
Current (I): | ? Enter current in Amperes(A) |
Resistance (R): | ? Enter resistance in Ohms(Ω) |
Voltage (V): |
Voltage (V): | ? Enter voltage in Volts(V) |
Current (I): | ? Enter current in Ampere(A) |
Resistance (R): |
Power
Voltage (V): | ? Enter voltage in Volts(V) | |
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Resistance (R): | ? Enter resistance in Ohms(Ω) |
Power (P): |
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Current (I): | ? Enter current in Amperes(A) | |
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Resistance (R): | ? Enter resistance in Ohms(Ω) |
Power (P): |
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Voltage (V): | ? Enter voltage in Volts(V) | |
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Current (I): | ? Enter current in Ampere(A) |
Power (P): |
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Voltage
Power (P): | ? Enter power in Watts(W) | |
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Current (I): | ? Enter current in Amperes(A) |
Voltage (V): |
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Power (P): | ? Enter power in Watts(W) | |
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Resistance (R): | ? Enter resistance in Ohms(Ω) |
Voltage (V): |
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Current (I): | ? Enter current in Amperes(A) | |
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Resistance (R): | ? Enter resistance in Ohms(Ω) |
Voltage (V): |
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Current
Voltage (V): | ? Enter voltage in Volts(V) | |
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Resistance (R): | ? Enter resistance in Ohms(Ω) |
Current (I): |
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Power (P): | ? Enter current in Amperes(A) | |
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Voltage (V): | ? Enter voltage in Volts(V) |
Current (I): |
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Power (P): | ? Enter power in Watts(W) | |
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Resistance (R): | ? Enter resistance in Ohms(Ω) |
Current (I): |
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Resistance
Voltage (V): | ? Enter voltage in Volts(V) | |
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Current (I): | ? Enter current in Amperes(A) |
Resistance (R): |
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Power (P): | ? Enter power in Watts(W) | |
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Current (I): | ? Enter current in Amperes(A) |
Resistance (R): |
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Voltage (V): | ? Enter voltage in Volts(V) | |
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Power (P): | ? Enter current in Ampere(A) |
Resistance (R): |
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Efficiency
η = (power out / power in) ×100%
Power out: | ? Enter power out | |
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Power in: | ? Enter power in |
Efficiency (η): |
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Cable resistance and conductance
R = (ρl)/A
Resistivity (ρ): | ? Enter resistivity in ohm-meters | |
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Length (l): | ? Enter length in meters | |
Cross-sectional area (A): | ? Enter cross-sectional area in square meters |
Resistance (R): |
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R = Rref (1 + α (T - Tref))
Resistance (Rref): | ? Resistance at reference temperature (Tref) | |
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Temp coefficient (α): | ? Temperature coefficient at Tref | |
Temperature (T): | ? Temperature | |
Temperature reference (Tref): | ? Temperature reference Tref |
Resistance (R): |
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Conductance: G = 1 / R
Resistance (R): | ? Resistance (R) |
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Conductance (G): |
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