I've this doubt regarding resistor: suppose I make a simple circuit with a power generator of 3 Volts and 1 Ampere and a resistor of $10 k\Omega$ I know from Ohm law that the current flow $i$ is:

$$I=\frac{V}{R}=\frac{3 V }{10000 \Omega}=0.3mA$$

So if I place my multimeter in series after the resistor I can measure exactly that current , and if I place the probe in parallel I can measure $3V$ so in this case I think that the resistor regulate the charge flow to 0.3 mA but in fact is the whole circuit to dissipate this current after the resistor regulated it, because I can see it passing through the multimeter ( and indeed 0.7 Amp give by the generator are not dissipated).

Shorting out the circuit with no resistance attached I can't measure an increase of temperature (I think because I'm not working with high power) but if a use a smaller resistor (e.g. $2 \Omega$) I can fell it getting hot so I infer that a smaller resistor dissipate more energy (in this case I've $1 Amp$ passing through it) but I think that this is no more a good charge regulator because it dissipate a lot of energy through Joule effect. So I don't know if exists materials that can be a good "charge regulator" (e.g. a good resistor) and material that can be good "energy dissipator" (e.g. for ma good heater). I've tried to make my homemade analogous resistor cutting $3,5 cm$ of a kanthal wire with a resistance of $57 \Omega / m$ but I can't measure correctly if this dissipate better the energy. Can anyone tell me what really do a resistor?

I've this doubt regarding resistor: suppose I make a simple circuit with a power generator of 3 Volts and 1 Ampere and a resistor of $10 k\Omega$ I know from Ohm law that the current flow $i$ is:

$$I=\frac{V}{R}=\frac{3 V }{10000 \Omega}=0.3mA$$

So if I place my multimeter in series after the resistor I can measure exactly that current , and if I place the probe in parallel I can measure $3V$ so in this case I think that the resistor regulate the charge flow to 0.3 mA but in fact is the whole circuit to dissipate this current after the resistor regulated it, because I can see it passing through the multimeter ( and indeed 0.7 Amp give by the generator are not dissipated).

Shorting out the circuit with no resistance attached I can't measure an increase of temperature (I think because I'm not working with high power) but if a use a smaller resistor (e.g. $2 \Omega$) I can fell it getting hot so I infer that a smaller resistor dissipate more energy (in this case I've $1 Amp$ passing through it) but I think that this is no more a good charge regulator because it dissipate a lot of energy through Joule effect. So I don't know if exists materials that can be a good "charge regulator" (e.g. a good resistor) and material that can be good "energy dissipator" (e.g. good heater). I've tried to make my homemade analogous resistor cutting $3,5 cm$ of a kanthal wire with a resistance of $57 \Omega / m$ but I can't measure correctly if this dissipate better the energy. Can anyone tell me what really do a resistor?

I've this doubt regarding resistor: I'm familiar with Ohm law but I'm not sure how can be applied to all types of resistors and I think sometimes oversimplify the problem. When I make a simple circuit with a power generator of 3 Volts and 1 Ampere and a resistor of $10 k\Omega$ I know that the current flow $i$ is:

$$I=\frac{V}{R}=\frac{3 V }{10000 \Omega}=0.3mA$$

So if I place my multimeter in series after the resistor I can measure exactly that current , and if I place the probe in parallel I can measure $3V$ so in this case I think that the resistor regulate the charge flow to 0.3 mA but in fact is the whole circuit to dissipate this current after the resistor regulated it.

Shorting out the circuit with no resistance attached I can't measure an increase of temperature (I think because I'm not working with high power) but if a use a smaller resistor (e.g. $2 \Omega$) I can fell it getting hot so I infer that a smaller resistor dissipate more energy (in this case I've $1 Amp$ passing through it) but I think that this is no more a good charge regulator because it dissipate a lot of energy through Joule effect. So I don't know if exists materials that can be a good "charge regulator" (e.g. for make a good resistor) and material that can be good "energy dissipator" (e.g. for make a good heater). I've tried to make my homemade analogous resistor cutting $3,5 cm$ of a kanthal wire with a resistance of $57 \Omega / m$ but I can't measure correctly if this dissipate better the energy.

I've this doubt regarding resistor: suppose I make a simple circuit with a power generator of 3 Volts and 1 Ampere and a resistor of $10 k\Omega$ I know from Ohm law that the current flow $i$ is:

$$I=\frac{V}{R}=\frac{3 V }{10000 \Omega}=0.3mA$$

So if I place my multimeter in series after the resistor I can measure exactly that current , and if I place the probe in parallel I can measure $3V$ so in this case I think that the resistor regulate the charge flow to 0.3 mA but in fact is the whole circuit to dissipate this current after the resistor regulated it, because I can see it passing through the multimeter ( and indeed 0.7 Amp give by the generator are not dissipated).

Shorting out the circuit with no resistance attached I can't measure an increase of temperature (I think because I'm not working with high power) but if a use a smaller resistor (e.g. $2 \Omega$) I can fell it getting hot so I infer that a smaller resistor dissipate more energy (in this case I've $1 Amp$ passing through it) but I think that this is no more a good charge regulator because it dissipate a lot of energy through Joule effect. So I don't know if exists materials that can be a good "charge regulator" (e.g. a good resistor) and material that can be good "energy dissipator" (e.g. for ma good heater). I've tried to make my homemade analogous resistor cutting $3,5 cm$ of a kanthal wire with a resistance of $57 \Omega / m$ but I can't measure correctly if this dissipate better the energy. Can anyone tell me what really do a resistor?