Advertisements
Advertisements
प्रश्न
Define the following:
Semiconductors
Advertisements
उत्तर
Semiconductors: Substances whose resistance decreases with the increase in temperature are named as semiconductors. E.g. manganin, constantan etc.
APPEARS IN
संबंधित प्रश्न
A given wire of resistance 1 Ω is stretched to double its length. What will be its new resistance?
A wire of length 5 m has a resistance of 2.0 Ω calculate:
(a) the resistance of wire of length 1 m
(b) the equivalent resistance if two such wires each of length 2 m are joined in parallel.
(c) the resistance of 1 m length of wire of same material but of half diameter.
A wire is passed through a piece of cardboard as shown in fig .. An electric current flows vertically down the wire and then flows back up. The two sections of the write are observed to repel each other.
(a) Wi th the aid of a diagram, describe how you would plot the magnetic field lines on the card .

(b) Sketch the magnetic field patterns around both the sections of the wire. Use your sketch to explain why the two sections repel each other.
(c) The repulsive force between the two sections is small. What changes could be made to increase it?
Calculate the current in a wire if a charge of 1500 coulomb flows through it in 5 minutes.
Electric current is defined as:
In electrolytes, the ions carrying charge move toward:
In ionised gases (plasma), the charge carriers are:
In a vacuum, the particles that can act as charge carriers are:
