If the length of a cable is doubled, its capacitance
A. Becomes one-fourth
B. Becomes one-half
C. Becomes double
D. Remains unchanged
Answer: Option C
Solution (By Examveda Team)
The correct answer is (C) Becomes doubleHere's why:
Capacitance (C) of a cable is determined by the following factors:
* The dielectric constant of the insulation material.
* The area of the conductors.
* The distance between the conductors (thickness of insulation).
* The length of the cable.
Think of a cable like a parallel plate capacitor.
The formula for capacitance is roughly:
C = (ε * A) / d
Where:
ε is the permittivity (related to the dielectric constant).
A is the area of overlap of the conductors.
d is the distance between the conductors.
When the length of the cable is doubled, it's like increasing the area of overlap (A) between the conductors.
Imagine connecting two identical capacitors in parallel.
The total capacitance doubles.
Therefore, if you double the length of the cable, you effectively double the capacitance.
This Question Belongs to Electrical Engineering >> Electrical Cables
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The capacitance of a single core cable is given by
C
l
=
2
π
ϵ
ln
(
R
r
)
F
/
m
l is length
R is the outer radius of the cable
r is the inner radius of the cable
The capacitance is directly proportional to the length of the cable.
Hence, If the length of the cable is doubled, then its capacitance C will be double.