PHYSICS · Multi-part · CBSE · Physics · Current Electricity · Current Electricity
Problem
Two solid cylindrical sections, A and B, are soldered end-to-end to create a composite resistor of uniform radius 1.0 mm.
• Section A: length 3.0 cm, resistivity 2.0×10−6Ω⋅m
• Section B: length 5.0 cm, resistivity ρB (unknown)
When connected across a power supply, the measured total resistance of the composite resistor is 0.50 Ω.
(a) Write an expression for the total resistance of the composite resistor in terms of ρB and the given numerical values.
(b) Determine the numerical value of ρB.
(c) If a steady current of 2.0 A flows through the composite resistor, calculate the power dissipated in Section B.