The filament of a bulb glows when current flows through it but the wires connected to it do not. Explain.

When does a bulb glow ?

Direct current cannot flow through.

A solenoid is connected to a battery so that a steady current flows through it. If an iron core is inserted into the solenoid, will the current increase or decrease ? Explain.

What is cause of heat produced in a conductor when current flows through it?

A wire connected to a bulb does not glow, whereas the filament of the bulb glows when the same current flows through them.Why?

How many time does the current flowing in an electric bulb becomes zero in one second? Explain.

In a wire of cross-section radius r, free electrons travel with drift velocity v when a current I flows through the wire. What is the current in another wire of half the radius and of the same material when the drift velocity is 2v?

What happens when a strong current is passed through a semiconductor? Explain.