Question
Hi, I am wondering about:
Consider the copper (Cu) and aluminum (Al) wires connected together as shown in the figure below and carrying a 5.0A current to the right. The right side of the aluminum wire is assumed to be at zero potential (0 V). Find: the resistance of the Cu wire; the resistance of the AI wire; the difference of potential across the two-wire combination; and. the difference of potential across the Cu wire. Consider a copper wire 1 mm in diameter providing the power needed to run an appliance drawing 4.8 kW at 12 V. Assuming that no heat is radiated away from the wire while the current flows: What will the temperature of the wire be after the current has run for 1 second through the wire? What will the physical condition of the wire be at that tune? (The wire was initially at 20 degree C - all data needed to solve this problem can be found in the book, however, not necessarily in the chapters dealing with resistances and currents.
Explanation / Answer
Resistance = resistivity( length/area of crossection )
Here area= pi D^2/4 (circular) and length given 1m each
We need resistivity of cu &Al to complete calculation (which may found in your textbook)
After finding resistance of cu & Al they are in series so Reff = Rcu + R Al
C) potential difference = IReff = 5(Rcu + R Al)
D) Vcu = IRcu = 5Rcu