In an electron microscope, the electrons are accelerated by a voltage of 14kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would

In an electron microscope, the electrons are accelerated by a voltage

1.	In an electron microscope, the electrons are accelerated by a voltage of 14kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would
Answer» INCREASE by 2 times decrease by 2 times decrease by 4 times increase by 4 times Solution :At voltage, V=14 kV de-Broglie wavelength of ELECTRON, `lambda=(12.3)/SQRT(14000) Å=0.104 Å` At voltage, V=224kV `lambda.=(12.3)/sqrt(224000) Å=0.026Å` `lambda/(lambda.)=(0.104)/(0.0260)=4 RARR 4lambda. rArr lambda.=lambda/4`

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In an electron microscope, the electrons are accelerated by a voltage of 14kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would

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