Two identical resistors of R0 = 30 ? are connected head-to-tail.
A.) Express the resistance R0 of one of the resistors in terms of the resistivity ?, length L, and the cross section area A.
B.) When the two resistors are connected head-to-tail, consider them as a single resistor. Which of the three quantities ?, L, A has been changed?
C.) Write an expression for the new length in terms of the old length L.
D.) Calculate the total resistance R of the two resistors in ?.