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प्रश्न
Each of the resistance shown in figure has a value of 20 Ω. Find the equivalent resistance between A and B. Does it depend on whether the point A or B is at higher potential?
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उत्तर
According to the Wheatstone bridge principle, if the bridge is balanced, then the current flow across the central resistor is zero. So, to simplify the circuit, we can remove the central resistor.
The given circuit is also balanced, so there is no current through the diode.
Hence, the net resistance of the circuit is given by
\[R_P = \frac{R_1 R_2}{R_1 + R_2}\]
\[\text{For } R_1 = R_2 = R, \]
\[ R_P = \frac{R}{2} = \frac{40}{2}\]
\[ \Rightarrow R_P = 20 \Omega\]
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संबंधित प्रश्न
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I = `"I"_0 exp ("eV"/(2"k"_"BT") - 1)`
where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, kBis the Boltzmann constant (8.6×10−5 eV/K) and T is the absolute temperature. If for a given diode I0 = 5 × 10−12 A and T = 300 K, then
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(d) What will be the current if reverse bias voltage changes from 1 V to 2 V?
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Answer in detail.
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