The half-life of the radioactive radon is 3.8 days. The time, at the end of which 1/20th of the radon sample will remain undecayed, is (given $log_{10} e = 0.4343$)
- 3.8 days
- 16.5 days
- 33 days
- 76 days
The Correct Option is B
Solution and Explanation
The correct option is(B): 16.5 days.
Using \(N=N_0e^{-\lambda t}\)
Where \(\lambda=\frac{1n2}{t_{1/2}}=\frac{1n(2)}{3.8}\)
\(\therefore\) \(\frac{N_0}{20}=N_0e^{-\frac{1n(2)}{3.8}}t\)
Solving this equation with the help of given data we find :
t = 16.5 days.
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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.