An electric current flows along a wire PQ. The variation of current density is shown in the graph. Which of the following statements could explain the variation?
Text Solution
Verified by ExpertsThe correct answer is:
A
The current density at 
is higher than at 
. For the same current flowing through the metallic conductor 
, the cross-sectional area at 
is narrower than at 
. The resistance per unit length 
is given by 
Where 
is the resistivity and 
is the cross-sectional area of the conductor 
. Thus, 
is inversely proportional to the cross-sectional area 
of the conductor.
Prepare Smarter with CGP Edu
Get practice questions, solutions, and test series in one place.
Write a Review
Share your experience with this question and solution.
Commentary
Send your comment, doubt, correction, or feedback to admin.
Similar Questions
Explore conceptually related problems
The balancing length for a cell is 560 cm in a potentiometer experiment. When an external resistanc…
The series combination of two batteries, both of the same emf 10V, but different internal resistanc…
Four resistances of 15 Ω Ω , 12 Ω Ω , 4 Ω Ω and 10 Ω Ω respectively in cyclic order to form Wheatst…
Match the following:
The following table gives the lengths of four copper rods at the same temperat…
Match the statements in Column I with the current element in Column II
Column - IColumn - II(A)Curr…
A continuous beam of electrons emitted by a heating filament are accelerated in free space by an el…