# As the cable length increases, there is

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As the cable length increases, there is
1. less insulation resistance and more leakage current
2. more insulation resistance and less leakage current
3. less insulation resistance and less leakage current
4. more insulation resistance and more leakage current

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Correct Answer - Option 1 : less insulation resistance and more leakage current

Concept:

Insulation resistance:

• Insulation resistance is defined as the ratio of applied direct voltage across insulation to the corresponding current flowing through it
• The current flow through insulation is called leakage current
• Leakage resistance or insulation is the opposition that a substance offers to the flow of leakage current

Insulation resistance of the cable is given by

$R = \frac{\rho }{{2\pi l}}\ln \left( {\frac{{{r_2}}}{{{r_1}}}} \right)$

Where ρ = resistivity of the material

l = length of cable

r2 = radius of the outer layer of cable

The resistance of insulation is inversely proportional to its length.

Application:

As the insulation resistance is inversely proportional to the cable length, with the increase in cable length, the insulation resistance decreases.

As the insulation resistance decreases, leakage current will increase.