Medium INTEGER +4 / -1 PYQ · JEE Mains 2022

The wavelength of an electron and a neutron will become equal when the velocity of the electron is $x$ times the velocity of neutron. The value of $x$ is ____________. (Nearest Integer)

(Mass of electron is $9.1 \times 10^{-31} \mathrm{~kg}$ and mass of neutron is $1.6 \times 10^{-27} \mathrm{~kg}$ )

Answer (integer) 1758

Solution

$$\lambda_{e}=\frac{h}{m_{e} \times V_{e}}, \quad \lambda_{N}=\frac{h}{m_{N} \times V_{N}}$$ <br/><br/> $\lambda_{e}=\lambda_{N}$ When $V_{e}=x V_{N}$ <br/><br/> $\frac{1}{m_{e} V_{e}}=\frac{1}{m_{N} \times V_{N}}$ <br/><br/> $\frac{m_{N}}{m_{e}}=\frac{V_{e}}{V_{N}}=x$ <br/><br/> $x=\frac{1.6 \times 10^{-27}}{9.1 \times 10^{-31}}$ <br/><br/> $=0.17582 \times 10^{4}$ <br/><br/> $\simeq 1758$

About this question

Subject: Chemistry · Chapter: Atomic Structure · Topic: Bohr's Model

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