Why are three 1k ohm resistors used in parallel when a standard value 330 ohm resistor is available?

Question

In a circuit using a variable power supply, why use three 1k Ohm resistors in parallel then in series to a diode rather than a 330 ohm resistor in series with the diode? This is for a intro circuits lab and all we did was measure the voltage from the source, then from the diode, graph this and show that I/V is not linear and that it is exponential. Under report it states exactly, "The graph of data and discussion of data must be computer generated. Why are three 1k ohm resistors used in parallel when a standard value 330 ohm resistor is available? Include your answers in the report."

I'm completely stumped as to the reason. Power dissipation seems unlikely as the current out of three 1k ohm resistors in parallel is similar to that from the current out of a single 330 ohm. Using P=iV wil yield approximately the same results. In a circuit using a variable power supply, why use three 1k Ohm resistors in parallel then in series to a diode rather than a 330 ohm resistor in series with the diode? This is for a intro circuits lab and all we did was measure the voltage from the source, then from the diode, graph this and show that I/V is not linear and that it is exponential. Under report it states exactly, "The graph of data and discussion of data must be computer generated. Why are three 1k ohm resistors used in parallel when a standard value 330 ohm resistor is available? Include your answers in the report."

I'm completely stumped as to the reason. Power dissipation seems unlikely as the current out of three 1k ohm resistors in parallel is similar to that from the current out of a single 330 ohm. Using P=iV wil yield approximately the same results. In a circuit using a variable power supply, why use three 1k Ohm resistors in parallel then in series to a diode rather than a 330 ohm resistor in series with the diode? This is for a intro circuits lab and all we did was measure the voltage from the source, then from the diode, graph this and show that I/V is not linear and that it is exponential. Under report it states exactly, "The graph of data and discussion of data must be computer generated. Why are three 1k ohm resistors used in parallel when a standard value 330 ohm resistor is available? Include your answers in the report."

I'm completely stumped as to the reason. Power dissipation seems unlikely as the current out of three 1k ohm resistors in parallel is similar to that from the current out of a single 330 ohm. Using P=iV wil yield approximately the same results.

Explanation / Answer

It may be to increase the Power dissipation.

If you need 330 ohm resistor then you may use three 1K ohm resistors in parallel for getting 330ohm resistor.

According this formula:

1/Rt = 1/Ra + 1/Rb + 1/Rc

Ra = 1K

Rb = 1K

Rc = 1K

where K=10^3

then Rt = 330ohm

The basic mean to use resistor in parallel to increase the current path.

so if you are gonna use three 1K ohm resistance in parallel rather just 330 ohm. Then definitely increase the current path.

and in result of this operation you have more Current rating of your Power Supply.

simply you may speak:

when you required more Current rating equipment. so you do perform Parallel operation.

on the other hand if you require more Voltage rating equipement you do perform Series operation.

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