JEE MAIN - Physics (2021 - 26th February Morning Shift - No. 15)
Given below are two statements : one is labeled as Assertion A and the other is labelled as Reason R.
Assertion A : An electron microscope can achieve better resolving power than an optical microscope.
Reason R : The de Broglie's wavelength of the electrons emitted from an electron gun is much less than wavelength of visible light.
In the light of the above statements, choose the correct answer from the options given below :
Assertion A : An electron microscope can achieve better resolving power than an optical microscope.
Reason R : The de Broglie's wavelength of the electrons emitted from an electron gun is much less than wavelength of visible light.
In the light of the above statements, choose the correct answer from the options given below :
A is false but R is true.
Both A and R are true but R is NOT the correct explanation of A.
Both A and R are true and R is the correct explanation of A.
A is true but R is false.
Açıklama
Resolution limit ($$\Delta$$$$\theta$$) = $${{1.22\lambda } \over d}$$
Resolution power = $${1 \over {{\mathop{\rm Re}\nolimits} solution\,\lim it}}$$
$$ \therefore $$ Resolution power $$ \propto $$ $${1 \over \lambda }$$
Since, wavelength of electron is much less than visible light, its resolving power will be much more.
Resolution power = $${1 \over {{\mathop{\rm Re}\nolimits} solution\,\lim it}}$$
$$ \therefore $$ Resolution power $$ \propto $$ $${1 \over \lambda }$$
Since, wavelength of electron is much less than visible light, its resolving power will be much more.