﻿ St. Mary's H.S. Physics - Elementary Charge Notes

Where did the charge go?

The charge went into the glass.

See Leyden Jar at Wikipedia

#27 - Elementary Charge - smallest charge known to exist in nature

All
Charges
come in whole number multiples of

1.6 x 10
-19 Coulombs

p

+1.6 x 10-19 C

(Reference)

e-

-1.6 x 10-19 C

(Reference)

Ex) Object has 4 p, 1 e-, charge?

+ 3 elem. charges or ...

+ 4.8 x 10-19 C

Ex) How many excess charges are there in an object with a charge of
-9.6 x 10–19 C?

6 excess electrons

Divide by
1.6 X 10
-19
Coulombs

To find # of

elementary charges

 Ex) A metal sphere -1.1 × 10-6 C. How many more electrons than protons are on the sphere? a) 1.8 × 1012 b) 5.7 × 1012 c) 6.9 × 1012 d) 9.9 × 1012

Ratio

1 elementary charge

1.6 X 10-19 coulombs

Divide by 1.6 × 10-19 C

 Scientific Notation/TI83Plus

-1.1 × 10-6 C

(1.6 × 10-19 C)

c) 6.9 × 1012 electrons

 Ex) An object can not have a charge of a) 3.2 x 10-19 C b) 4.5 x 10-19 C c) 8.0 x 10-19 C d) 9.6 x 10-19 C

b) 4.5 x 10-19 C

(not an even multiple
of 1.6 x 10-19
C)