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hm's equation calculator

This page tells you how to download and use the Ohm's equation calculator program

Click to Download

Internet Explorer will respond with a dialog box. You can decide whether to save the program to disc and run it later, or to open it straight away. Either way, there may be a further dialog box, giving dire warnings about downloading software from the internet. (DOCTRONICS knows of no problems with the program, but no guarantee is implied.)

The Ohm's equation calculator can be copied and distributed freely, but remains copyright ©. Distribution for profit seems unlikely, but is expressly forbidden.

The program was written using Borland Delphi 2.0.

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How to use the program

1. Calculating voltage:

This uses the formula:

When the program is first loaded, the Tab for is automatically selected. Enter a value for the current, I, enter a value for the resistance, R, and then click

Here is the calculation for I = 10 mA, R = 1.2 :

calculating voltage from V=IR

The button has been clicked and the answer, 12 V, is highlighted.

clicking V units, I units or R units at this stage will convert from one unit to another. For example, if you click the ohm radio button, 1.2 is converted to its equivalent in ohms:

The answer to the calculation is not altered.

On the other hand, you will sometimes want to enter current and resistance values in units other than the default ones of mA and . To get this to work, the measurement unit must be selected before the button is clicked for the first time.

Click on the I=V/R tab and then again on the V=IR tab to begin a new calculation.

Enter a value of 1.5 for current and then click the A radio button to select amps as the measurement unit. Now enter 10 as the resistance value and click the ohm radio button. Note that the values you entered are not changed.

Clicking gives the corresponding voltage, 15 V.

The radio buttons for V units, I units and R units function in this way when a new calculation is initiated, and operate in a different way once the result of the calculation has been made to appear.

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2. Calculating current:

Click on the I=V/R tab to change to the appropriate Ohm's equation:

calculating current from I=V/R

You enter the voltage and resistance in exactly the same way, and then click

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3. Calculating resistance:

Select the R=V/I Ohm's equation by clicking on the corresponding tab:

calculating resistance from R=V/I

Entering the voltage and current and then clicking will reveal the corresponding resistance.

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