A parallel beam of fast moving electrons is incident normally on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, which of the following statements is correct?

Question

A parallel beam of fast moving electrons is incident normally on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, which of the following statements is correct?

Infinity Learn · Accepted Answer

de Broglie wavelength of an electronλ$$=hp=hmvwhere$$ m is the mass and v is the speed of the electron respectively.If speed v of electron is increased, momentum p $$(=$$ $$mv)$$ will increase. Hence, wavelength λ will decrease.Angular width of the central maximum is θ$$0=2$$λawhere a is the width of slit.If λ  decreases, θ$$0$$ will decreaseTherefore, the correct statement is (a).

A parallel beam of fast moving electrons is incident normally on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, which of the following statements is correct?

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