0
You visited us 0 times! Enjoying our articles? Unlock Full Access!
Question

Answer the following question:
(a) A steady current flows in a metallic conductor of non-uniform cross-section. Which of these quantities is constant along the conductor: current, current density, electric field, drift speed?
(b) Is Ohms law universally applicable for all conducting elements?If not, give examples of elements which do not obey Ohms law.
(c) A low voltage supply from which one needs high currents must have very low internal resistance. Why?
(d) A high tension (HT) supply of, say, 6 kV must have a very large internal resistance. Why?

Solution
Verified by Toppr

(a) Since current is given to be steady, it is constant. The current density, electric field and drift speed are inversely proportional to area of cross section.
(b) No, examples of non-ohmic elements are vacuum diode,semiconductor diode, etc.
(c) By Ohms Law, I=V/R. Now, if current required is high, the voltage should be high and the resistance should be low. Hence, a low voltage supply from which one needs high currents must have very low internal resistance.
(d) Any high tension supply must have a large internal resistance, because, if the circuit is shorted (accidentally), the current drawn will exceed safety limits. This can be dangerous for human life and can cause fatal accidents.

Was this answer helpful?
1
Similar Questions
Q1

Answer the following questions:

(a) A steady current flows in a metallic conductor of non-uniform cross- section. Which of these quantities is constant along the conductor: current, current density, electric field, drift speed?

(b) Is Ohm’s law universally applicable for all conducting elements?

If not, give examples of elements which do not obey Ohm’s law.

(c) A low voltage supply from which one needs high currents must have very low internal resistance. Why?

(d) A high tension (HT) supply of, say, 6 kV must have a very large internal resistance. Why?

View Solution
Q2

A steady current flows in a metallic conductor of non uniform cross section .Explain which of these quantities is constant along the conductor and why? :current, current density, electric field and drift speed?

View Solution
Q3
A steady current flows in a metallic conductor of non-uniform cross-section. Which of the following quantities is constant along the conductor?
View Solution
Q4
A steady current flows in a metallic conductor of non uniform cross-section. The quantity that remains constant along the length of the conductor is
View Solution