Calculating Poynting Vector in Long Resistive Rod

AI Thread Summary
To calculate the Poynting vector for a long resistive rod, one must consider the rod's resistance, length, and radius while neglecting edge effects. The Poynting vector, defined as N = 1/μ₀ (E x B), requires knowledge of the electric field (E) and magnetic field (B), which are not provided in the problem. The discussion highlights confusion about how to initiate the calculations without these fields. Additionally, it emphasizes the need to relate the energy transfer rate between the rod and its surroundings to the power dissipated within the rod. Clarifying the electric and magnetic field conditions is essential for solving the problem effectively.
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Homework Statement



Consider a long resistive rod, exhibiting resistance R, of length l and radius r. Calculate the magnitude and direction of the Poynting vector (neglecting edge effects) and relate the rate of energy transfer between the rod and its exterior to the total power dissipated in the rod.


Homework Equations





The Attempt at a Solution



Not sure how to even go about starting this?! Any help please?

I know that N = 1/mu o E x B, but here we aren't given an E or B field?! What to do ?

Thanks!
 
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