A 100-cm-long copper wire of radius 0.50 cm has a potential
difference across it sufficient to produce a current of
3.0 A at 20°C. (a) What is the potential difference? (b) If
the temperature of the wire is increased to 200°C, what
potential difference

Question

A 100-cm-long copper wire of radius 0.50 cm has a potential
difference across it sufficient to produce a current of
3.0 A at 20°C. (a) What is the potential difference? (b) If
the temperature of the wire is increased to 200°C, what
potential difference

rock_mit182 · Answer

Using Kirchhoff’s rules, (a) find the current in each resistor
shown in Figure P18.23 and (b) find the potential difference
between points c and f.|dw:1426727327399:dw|

rock_mit182 · Answer

Could anyone give me a hand on this ?

anonymous · Answer

you have to do the too kirchov loops

anonymous · Answer

*two

rock_mit182 · Answer

counterclockwise ?

anonymous · Answer

it doesn't matter as long as your consistant

rock_mit182 · Answer

in this case Esub n doesn't have resistance

anonymous · Answer

70 +2000I + 3000(I2) -60 loop one

anonymous · Answer

60-3000(I2) + 80 + 4000(I3)

rock_mit182 · Answer

E1 + I1*r1 + I2 *r2 -E2 =0

anonymous · Answer

yeah

anonymous · Answer

is is dependent on which way the battery is pointed , but you get the idea

rock_mit182 · Answer

you mean if the current enter (-) or (+) into the battery ?

anonymous · Answer

yeah because of the law that the currents going into a joint equalls the current out of a joint

rock_mit182 · Answer

what i don't get is: -3000I2

anonymous · Answer

you have a 3000 ohm resistor that has a different current i2 . Ill draw it one sec

anonymous · Answer

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