In the absence of electric field, the paths of electrons between successive collisions with the positive ions in a metal are
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → straight lines
With no electric field, no force acts on a free electron between two collisions, so it moves with constant velocity, which means along a straight line.
At each collision with a positive ion its direction changes at random. The overall path is therefore a zig-zag made of straight pieces, with no net drift in any direction.
NCERT (2026-27):
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