Two cables of copper are of equal lengths. One of them has a single wire of area of cross-section A, while other has 10 wires of cross-sectional area \(\frac{A}{10}\) each. Give their suitability for transporting A.C. and D.C.
Two cables of copper are of equal lengths. One of them has a single wire of area of cross-section A, while other has 10 wires of cross-sectional area \(\frac{A}{10}\) each. Give their suitability for transporting A.C. and D.C.
- only multiple strands for A.C., either for D.C.
- only multiple strands for A.C., only single strand for D.C.
- only single strand for D.C., either for A.C.
- only single strand for A.C., either for D.C.
The Correct Option is A
Solution and Explanation
The major portion of the A.C. flows on the surface of the wire. So where a thick wire is required, a number of thin wires are joined together to give an equivalent effect of a thick wire.
Therefore multiple strands are suitable for transporting A.C. Similarly multiple strands can also be used for D.C.
Therefore, the correct option is (A) : only multiple strands for A.C., either for D.C.
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Concepts Used:
Current Electricity
Current electricity is defined as the flow of electrons from one section of the circuit to another.
Types of Current Electricity
There are two types of current electricity as follows:
Direct Current
The current electricity whose direction remains the same is known as direct current. Direct current is defined by the constant flow of electrons from a region of high electron density to a region of low electron density. DC is used in many household appliances and applications that involve a battery.
Alternating Current
The current electricity that is bidirectional and keeps changing the direction of the charge flow is known as alternating current. The bi-directionality is caused by a sinusoidally varying current and voltage that reverses directions, creating a periodic back-and-forth motion for the current. The electrical outlets at our homes and industries are supplied with alternating current.