Cressall

Power Resistors

Ohm’s Law at your fingertips!

How it works

Using Ohm's Law and the Power Rule, this is a well laid out and easy to use calculator for voltage, current and power. The interface makes it easy to ‘juggle’ the circuit variables until you get the combination you want. The key feature is that for ‘what-if?’ calculations you don’t need to re-enter the data every time you change one variable.
  • Enter a variable on the keypad and tap its category.
  • Enter a second variable and tap its category.
  • All four values are now calculated.
  • The last value entered is in bold and will be unchanged in the next calculation. To choose a different category as the fixed one, just tap it.
  • Enter another variable and the other two will recalculate.
Ohms law app

Download it now - it's free

 

What users say:

Superb Ohm's law calculator! Very user friendly, easy to perform multiple calculations, good stuff!

Great app. I tried a few apps before rating this one. This was the best and easiest to use.

Perfect for use at school, I can instantly use to help explain the basics to the students.

Great wee app. Great time saving device, as we had to manually configure wind turbine dump load values. Well done.

We use it to design all our resistors

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