What is the size of a electron microscope?

Answer 1

Curiously, this most common of atomic parts has only a fuzzy estimate of size.

Linus Pauling says "The radius of the electron has not been determined exactly, but it is known to be less than 1 X 10-13 cm".

So roughly the electron is 1/1000 the size of a proton. Maybe. But a cooler answer is-- physicists are annoyed by the question. A good case can be made for other sizes, even huge sizes....because the properties of the electron OTHER than it's size are the ONLY important ones. In fact the size of atomic pieces smaller than the nucleus usually does not matter at all....and may in fact have no meaning. After all, how do you propose to measure these guys?

The electron is known to be a point particle down to a limit of 10^-18m. It, as far as we know does not have a classical "size".

Answer 2

Because an electron is extremely small, there is no way of measuring its size directly. It has no known substructure, and it is defined or assumed to be a point particle with point charge and no spatial extent.

For everyday objects that can be measured with a ruler, a size can be stated accurately and unambiguously, but at the extremely tiny scale of subatomic particles, the very concept of size can become problematical and difficult to define. The question "how big" becomes entangled with considerations of how we intend to estimate the size when no direct measurement is possible. The various assumptions we make in deriving different size estimates can -- and do -- lead to a surprisingly wide range of results.

A number of size estimates for the electron have been derived from indirect evidence and theoretical models. These estimates extend over a rather wide range of values. The book "The Enigmatic Electron" by Malcolm H. MacGregor (Kluwer, 1992) gives these values for the electron's radius:

1. R(E) (point-like charge radius)-------------------<1 x 10-16 cm

2. R(0) (classical radius)--------------------------2.82 x 10-13 cm

3. R(C) (Compton sized electron)------------------3.86 x 10-11 cm

4. R(E) Effective (R(E) = 2/5 RC)-------------------1.5 x 10-11 cm

5. R(E) Effective - Corr (R(E) = XX R(C)-------------1.3 x 10-11 cm

6. R(H) (based on Compton radius)--------------------4 x 10-12 cm

7. R(H) (based on classical radius) -----------------4.09 x 10-12 cm

8. R(H) QM-Corrected (R(H) = (sqrt of 3)*R(C))----6.69 x 10-11 cm

9. Scattering results before 1992 imply--------------< 1 x 10-16 cm

10. Scattering results very recently imply------------< 1 x 10-18 cm

Results of an experiment published in 1988 give an upper limit for the electron's radius of 10-22 meters (Dehmelt, H. (1988). "A Single Atomic Particle Forever Floating at Rest in Free Space: New Value for Electron Radius". Physica Scripta T22: 102-10.)

We can, however, measure the mass of the electron with considerable precision; it is known to be 9.109383 x 10-28 gram. A proton weighs 1836 times as much.

Answer 3

Extremely small. They are so small, scientists don't even know where they are. They hover somewhere in the electron cloud, which is the place where they are supposed to be.

The mass is 9.10938188 * 10^-31 kilograms.

Answer 4

Size can vary from a small scanning electron microscopes (SEM), about the size of a tower PC case that sits on a table top, to a million volt transmission electron microscopes (TEM) that is several stories tall.

Answer 5

minus 260.000xy= smaller an air waves ( unable to see by the human eye

Answer 6

An electron is about .03 meters small. An electron is about .03 meters small.

Answer 7

An electron is 10-20 meters small. It is small.