Electronics & Software – Tips & Guide


Why is the voltage across resistors on an experiment slightly different from the calculations?

Why is the voltage across resistors on an experiment slightly different from the calculations?

the last band of the resistor is the load or + or – of the resistor, so that the resistance can vary in the resistor itself, in addition to the resistance of the solider seals, circuit boards and others resistors along the way. it can also vary from the power supply itself, a large load on the power supply will cause a voltage drop.

accuracy of your measuring tools (mm). internal resistance of your voltage source, which drops the supplied voltage once you have pulled a current.

tolerance of resistors There are different series available commercially with an accuracy of 10, 5 and 1% compared to the indicated value and the actual value.

resistance may not be a close tolerance and will therefore be slightly different. even 1% are just that, not dead.

your player may not read correctly

If yours is a low impedance meter at 10k per volt, it will not give the accuracy of a 10 megabyte. The

resistors are manufactured with a tolerance index that is generally between 1% and 10% – this means that the actual value may vary from this value by +/-.

Thus, a resistance with a tolerance of 10% sold in the form 1k (1000 ohms) could have a value between 900 and 1100 ohms.

If there are also active components in the circuit, these may also have manufacturing differences.

shows and demonstrates the difference between the theoretical and real aspects of this world.

The calculations reflect the snapshot of a theoretical value while the measured voltage is the actual instantaneous value that may have been affected by changes in conditions. ..

the difference can possibly be caused by the imperfect conditions caused by the resistance value, the resistance may have changed in value due to the temperature change caused by the current flowing through it ..

why the voltage between the resistors a slightly different experience of the calculations?

because nothing is accurate the resistors have tolerances. your 5v power supply is probably not exactly 5v. your meter has a precision that is not perfect. The LEDs can fall from a slightly different voltage to each other, and it depends a little bit on the exact current and temperature.

a semiconductor pn junction (light-emitting diodes, bipolar transistors) in direct polarization drops a voltage which depends on the amount of current, the temperature and the manufacturing method. the gain of a transistor can vary enormously from one transistor to another. Look at a spec sheet – it can give a beta value of 100 as a typical value, but in a range of 50 to 200.

your meter or oscilloscope, regardless of your voltage measurement, has a resistor that modifies the circuit. most dmms have an input resistor of 10m ohms (10 million ohms) and most oscilloscopes, when a 10x probe is used, have an input impedance of 10m ohms with 2 or 3 pf in parallel.