Engineering

Power, current and voltage

Enter any two of power, voltage and current to find the third.

Inputs

Leave the value you want to find blank.

Result

Current

40
Power
480
Voltage
12
Equivalent resistance
0.3

How it’s calculated

Formula

P=VIP = V I
Req=VIR_\text{eq} = \frac{V}{I}

With your numbers (converted to SI units)

I=480 W12 V=40 AI = \frac{480\,\text{W}}{12\,\text{V}} = 40\,\text{A}
Req=12 V40 A=0.3 ΩR_\text{eq} = \frac{12\,\text{V}}{40\,\text{A}} = 0.3\,\Omega

What it means

Electrical power is voltage times current. At FRC’s 12 V, every 100 W a mechanism draws is about 8.3 A from the battery. The equivalent resistance is what the load looks like to the supply at this operating point.

Assumptions

  • DC power; for motors this is electrical input power, not mechanical output.

Learn the concepts behind this on resources.simbotics.org · All formulas

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