# How to find average current of trapezium

1. Mar 26, 2015

### billy fok

Can anyone teach me how to find the average current of Trapezium???
i have attached the pic

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2. Mar 26, 2015

### uart

It's just the total area under the curve during one period (that is, the time integral of the current over one period), divided by the period.

You know the formula for the area under a trapezium?

3. Mar 26, 2015

### billy fok

hi.. i do not know the formula for the area under a trapezium... hope you are able to help me..

4. Mar 26, 2015

### uart

$$A = (a + b)\frac{h}{2}$$

Or in this case:

$$( I_{min} + I_{max} ) \frac{t_{on}}{2}$$

5. Mar 26, 2015

thanks