Question

a wire connected to a bulb doesn't glow whereas tge filament of the bulb glows when the same current is passed through them.why?

Answer 1

The main reason behind this is the difference in the
$\small \bold{resistance}$
of both.. the filament has a high resistance while the wire has a low resistance..

Answer 2

Because the wire does not have high resistivity while the filament of a bulb has high resistivity .
As we know heat produced is directly proportional to the resistance
$h = {i}^{2} rt$
so the high resistivity of the filament of a bulb produces more heat which helps the bulb to glow.

hope it helps u!