# Charge &amp; Coulomb’s Law A. Charge ```Charge &amp; Coulomb’s Law
A.
Charge
1.
is the source of the _________________ ______________
2.
can neither be _____________ nor _____________ only
______________________
3.
has the SI units of _________________________
4.
is _____________________ in units of _________________
5.
comes in only __________ ___________ which are called
___________ and ____________.
6.
Like charges __________ and unlike charges ____________
B.
Terminology
1.
Neutral body is a body with ___________ amounts of
________ and __________ charge.
2.
__________________ is a material in which charge is free to
flow.
Type 1:
Type 2:
3.
________________ is a material in which charges are not
free to move.
4.
_______________ are materials between insulators and
conductors in the difficulty for charges to move.
C.
1.
Two Ways to Charge a Body
_____________ is the transfering of ______________
between two bodies due to ________________ between the
bodies.
2.
__________________ is the influencing of _____________
on a body due to a _______________ ____________ that is
nearby but _________ ______________ the 1st body.
D.
Electric Force and Gravity
Definitions:
Electric force is the force between two bodies due to
charge on the bodies
-
Gravitational force is the force between two bodies
due to the mass of the bodies
1.
Universal Law of Gravity (point/spherical masses)
2.
Coulomb’s Law (point/spherical charges)
These two formulas are important because more complicated
problems can be broken down into collections of point
masses/charges and the forces summed using superposition.
3.
Comparison
Properties
Source
Type
Range
Strength
Electric
Gravity
Mass
Attractive
∞
Weak
Problem 1:
Three charges are situated as shown below. Find
the net force upon the 1.0 nC charge.
2.0 C
0.5 m
1.0 nC
0.5 m
2.0 C
1.0 m
Solution:
Physics -
Given:
1.
Draw a Free Body Diagram
2.
Find Magnitude of Each Force
Equations:
3.
Find the Components of the Forces
4.
5.
Draw the Resultant Vector Force
6.
Find the magnitude and angle of resultant using the
vector force diagram.
Problem 15.5 in Serway/Faughn
The nucleus of 8Be, which consists of 4 protons and 4 neutrons, is very unstable and
spontaneously breaks into two alpha particles (helium nuclei, each consisting of 2
protons and 2 neutrons). (a) What is the force between the two alpha particles when
they are 5.00x10-15m apart, and (b) what will be the magnitude of the acceleration of
the alpha particles due to this force? Note the mass of an alpha particle is 4.0026u.
Note: 1.007276 u = 1.67265x10-27 kg (Back of textbook)
Figure:
Physics:
Given:
Soultion:
Equations:
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