Question

Assuming that voltage remains constant, what happens to the current in a filament if it is replaced by a thinner wire?

A. The current increases.
B. The current decreases.
C. The current is not affected by a change in filament thickness.
D. The current alternates between high and low values.

Answer 1

B, I would presume since you don't have enough thickness in your wire as you did before.

Answer 2

If the new filament wire is made of the same substance as the old one
but is thinner, then its resistance is higher than the original one.

When constant voltage is applied to a greater resistance, the current
decreases.