A potential barrier of 0.4 V exists across a p-n junction. An electron enters the junction from the n-side with a speed of 6.0 × 105 ms–1. The speed with which electrons enters the p side will be
\(\frac{x}{3} × 10^5\) ms-1
the value of x is _________.
(Give mass of electron = 9 × 10–31 kg, charge on electron = 1.6 × 10–19 C)
A potential barrier of 0.4 V exists across a p-n junction. An electron enters the junction from the n-side with a speed of 6.0 × 105 ms–1. The speed with which electrons enters the p side will be
\(\frac{x}{3} × 10^5\) ms-1
the value of x is _________.
(Give mass of electron = 9 × 10–31 kg, charge on electron = 1.6 × 10–19 C)
Correct Answer: 14
Solution and Explanation
The correct answer is 14
Conserving energy,
\(\frac{1}{2} mv² = \frac{1}{2} m ( 6 × 10^5)^2 - 0.4eV\)
\(⇒ v = \sqrt{( 6 × 10^5)^2 - \frac{2 × 1.6 × 10^{-19} × 0.4}{9 × 10^{-31} }}\)
\(=\sqrt{36 × 10^{10} - \frac{1.28}{9} × 10^{12}}\)
\(⇒ v = \frac{14}{3} × 10^5 m/s\)
⇒ x = 14
There , the speed will be 14 m/s
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Concepts Used:
Semiconductors
Semiconductors are a crystalline solid materials, whose electrical conductivity lies between a conductor and an insulator. Semiconductors are mainly used in the manufacturing of electronic devices like capacitors, transistors, diodes, Integrated circuits, etc.
Properties of Semiconductor:
- Semiconductor acts like an insulator at Zero Kelvin. On increasing the temperature, it works as a conductor.
- Due to their exceptional electrical properties, semiconductors can be modified by doping to make semiconductor devices suitable for energy conversion, switches, and amplifiers.
- Lesser power losses.
Uses of Semiconductor:
- Semiconductors are widely used in manufacturing electronics devices like transistors, diodes, sensors, integrated circuits.
- Semiconductors are widely used in all electronic devices, like mobile phones, digital cameras, communication devices, trains, ATMs, etc.