EE MCQ

SSC JE Electrical 2019 with solution SET-1
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Reflected Light/Incident Light =

The ratio of luminous flux leaving the surface (Reflected Light) to the luminous flux incident on it (Incident Light) is known as the reflection factor.

Reflection Factor = Reflected light/Incident light

The value of the Reflection factor is always less than 1.

Related Question

SSC JE Electrical 2019 with solution SET-1
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In the circuit shown, find the equivalent resistance between A and B.

The resistance R3 & R4 are connected in series

= (30 + 70) = 100Ω

Now three resistor i.e 100Ω, 100Ω & 50Ω is connected in parallel

1/Rp = 1/100 + 1/100 + 1/50

Rp = 100/4 = 25 Ω

Resistance 50Ω and 25Ω are connected in series.

Rtotal = (50 + 25)Ω

Rtotal = 75Ω

SSC JE Electrical 2019 with solution SET-1
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Two inductors of 4H and 6H are connected in series. The equivalent inductance of this combination is

Total inductance when inductor are connected in series

L = L1 + L2

L = 4 + 6 =10H

SSC JE Electrical 2019 with solution SET-1
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The ratio of conductor voltage and the voltage across the disc nearest to the conductor multiplied by the number discs are

The non -uniformity in the voltage distribution over a string of suspension insulators is expressed in terms of a parameter called “string efficiency“.

The voltage across the unit nearer to the conductor is more than the voltage in the unit nearer to the support. This unequal potential distribution over the string is expressed in terms of string efficiency.

The efficiency of a string is defined as the ratio of voltage across the whole string to the product of the number of discs and the voltage across the disc nearest to the line conductor. Mathematically, it can be expressed as,

Where n = Number of the unit in the string

The more the value of the string efficiency, the more uniform is the voltage distribution across the string. For the ideal case, the string efficiency is 100% and the voltage across each disc of the string is equal. Practically various methods are used to obtain string efficiency as high as possible.