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Home Concept Builders Electric Circuits Parallel Circuits - ∆V = I•R Calculations Directions

Parallel Circuits - ∆V = I•R Calculations - Directions

Using the Parallel Circuits - ∆V=I•R Calculations Concept Builder is quite simple. You will be presented with a diagram of a simple or a parallel circuit and a table of numerical values associated with the battery voltage, the resistance values, and the current at various locations. Some cells of the table are blank and you will have to use ∆V = I•R and circuit principles to solve for the blank cells. You can consider each row of the table as a separate problem; resistor values and battery voltage values vary from row to row. Only information from that row can be used to determine the unknown values. One row is not dependent upon other rows.

To enter numbers into the table, simply tap on a table cell. A Number Pad pops up. You can use the Number Pad to enter answers into the table cell. Once complete, you can tap the Close Number Pad button (at the bottom of the number pad) or tap on a different table cell. Once you are satisfied with your answers, tap on the Check Answers button. Your answers will be evaluated and feedback will be given. Feedback is given in terms of color-coded table cells. Table cells color-coded green were correctly answered and cannot be changed again. If an answer is incorrect, then the table cell will be color-coded red.

The Concept Builder keeps track of the number of misses. A miss is considered any value that is entered into a cell and evaluated as incorrect. If a cell value is incorrect on the first attempt and not changed, it would be marked as a miss on the second attempt. If you do not wish to check that incorrect value again, then you would have to remove the value (tap on the cell to open the Number Pad and tap on the C or Clear button) before the next time that your check your answers.

Once all table cells are accurately completed, your Health Percent is shown. The Health Percent is based upon the number of misses. The formulas for calculating this are:

Apprentice Difficulty Level: Health Percent = 100 - 3*Number of Misses

Master Difficulty Level: Health Percent = 100 - 2*Number of Misses

Wizard Difficulty Level: Health Percent = 100 - 2*Number of Misses


Your Health Percent is displayed on the Main Menu. If you wish to repeat the Difficulty Level to improve your Health Percent, you can tap on the provided button to do so. Your best Health Percent is always displayed on the Main Menu. If you repeat a difficulty level and do worse the second time, it is the best Percent that will be displayed.

Concept Builder Teacher Notes