kinetic energy

asked by @brianap13 • 12 months ago • Chemistry • 5 pts

To resolve an object in an electron microscope, the wavelength of the electrons must be close to the diameter of the object. What kinetic energy must the electrons have in order to resolve a protein molecule that is 7.80 nm in diameter? Take the mass of an electron to be 9.11× 10–31 kg.

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2 answers

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just change the wavelength to 7.80

answered by @sarag12 • 12 months ago

Hi there! For the complete solution:

Wavelength = 7.8x10^-9 m

DeBroglie Equation --> wavelength= h/mv

v=h/m(wavelength)

v= (6.626x10^-34)/(9.11x10^-31)(7.8x10^-9)

v= 93,247 m/s

KE= 0.5 mv^2

KE=0.5(9.11x10^-31)(93,247)^2

KE=3.9606x10^-21 J

answered by @reyn • 12 months ago