Potential difference required in an electron microscope to give an electron wavelength of 4. 5 nm will be 0.063 V.
The difference in potential between two points that represents the work involved or the energy released in the transfer of a unit quantity of electricity from one point to the other is called potential difference.
The wavelength of an electron is calculated for a given energy (accelerating voltage) by using the de Broglie relation between the momentum p and the wavelength λ of an electron
lambda = 4.5 nm = 4.5 * 
m
h = 
J s
e = 1.6 * 
C
m = 9.1 * 
kg
Energy = eV
lambda = h / 
= h / 
= 
/ (2m (eV))
V = / (2 m e )
V = 
/ 2 * 9.1 * * 1.6 * * 
V = 0.063 V
To learn more about wavelength of an electron here
brainly.com/question/17295250
#SPJ4
When using parallax, astronomers calculate distance from the sun and not earth to improve on the accuracy of their measurement, since parallax angle decreases as star distance increases.
<h3>
What is parallax distance?</h3>
Parallax enables astronomers to measure the distances of far away stars by using trigonometry.
<h3>Why does astronomers measure parallax distance from sun?</h3>
As the distance of star increases, the parallax angle decreases, and great degree of accuracy is required for its measurement.
So taking a refence from the earth instead of the sun will impact the accuracy of their measurement.
Thus, when using parallax, astronomers calculate distance from the sun and not earth to improve on the accuracy of their measurement, since parallax angle decreases as star distance increases.
Learn more about parallax distance here: brainly.com/question/2128443
#SPJ1
Answer:
The state of being without reliablr access to a sufficient quantity of affordable, nutritious food
Dr.phil can help you with that answer also the answer is 21.3
Angle of incidence is the angle when the light strikes an object while angle of reflection is the angle produced when the light strikes off/reflects from the object.
The relation between these two is that both the angles are equal.
The law of reflection states that when a ray of light reflects off a surface, the angle of incidence is equal to the angle of reflection.
Hope this helps!
