In an electron microscope, the resolution that can be achieved is of the order of the wavelength of electrons used. To resolve a width of 7.5 × 10-12m, the minimum electron energy required is close to :

Question

In an electron microscope, the resolution that can be achieved is of the order of the wavelength of electrons used. To resolve a width of 7.5 × 10-12m, the minimum electron energy required is close to : (A) 100 keV (B) 500 keV (C) 25 keV (D) 1 keV

Tardigrade Admin · Accepted Answer

λ = (h/p) λ = 7.5 ×10-12 P = (h/λ) KE = (P2/2m) = ((h/λ)2/2m) = ( (6.6 ×10-34/7.5 ×10-12) /2 ×9.1 ×10-31) KE = 25 Kev

Q. In an electron microscope, the resolution that can be achieved is of the order of the wavelength of electrons used. To resolve a width of $7.5 \times 1 0^{- 12} m$ , the minimum electron energy required is close to :

100 keV

500 keV

25 keV

1 keV

$λ = \frac{h}{p} {λ = 7.5 \times 1 0^{- 12}}$
$P = \frac{h}{λ}$
$K E = \frac{P ^{2}}{2 m} = \frac{( h / λ ) ^{2}}{2 m} = \frac{{ \frac{6.6 \times 1 0 ^{- 34}}{7.5 \times 1 0 ^{- 12}} }}{2 \times 9.1 \times 1 0 ^{- 31}}$
$K E = 25 Ke v$

Q. In an electron microscope, the resolution that can be achieved is of the order of the wavelength of electrons used. To resolve a width of 7.5×10−12m, the minimum electron energy required is close to :