Question

ANSWER PLEASE If 18 meters of high-resistance wire with a diameter of 1.2 mm has a resistance of 10 ohms, what is the resistance of 27 m of the same type of wire with a diameter of 1.5 mm?

Answer 1

can somebody please help me by explaining it and show me the answer and how to get it

Answer 2

the resistivity of a resistor is given by
resistivity = (RA)/L
where
R=resistance
A=Cross sectional area of wire
L length of the wire
The resistivity of the given type of wire can be assumed to be constant here, So
\[\frac{ R1 A1 }{ L1 } = \frac{ R2 A2 }{ L2 }\]
R2 is what youre after so you can rearange to get
\[\frac{ R1 A2 L2 }{ L1 A2 } \]
then just plug in the numbers in the question.
that cool?