I conducted an experiment involving a 555IC timer circuit and the hypothesis investigated the frequency and period of the LED connected.(adsbygoogle = window.adsbygoogle || []).push({});

Using the formula for frequency; 1.44/(Ra + 2Rb)C

where R1= 1000R

R2= 10000R

C = 10uF

the frequency equals 6.857 (rounded value)

now using data studio (a reliable computer program which can graph the frequency) the frequency equals 1.429 (rounded value)

Now, ive taken into consideration the 5% tolerance of the resistors used, and the variation on the capacitor as these may account for the changed frequency but this still doesnt explain this rather large difference in expected frequency and observed frequency....

Any explanations for this large difference????

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# 555 timer circuit; frequency variation

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