This document defines key electrical concepts like voltage, electromotive force, potential difference, charge, and current. It establishes the relationship between charge and current and explains that current is the flow of electric charge over time. Finally, it outlines how direct current is applied to x-ray tubes to generate electrons that strike the anode and produce x-rays.

2.  Define; voltage, electromotive force (EMF),
potential difference (PD), charge and current.
 Determine the relationship between charge
and current.
 Outline the application of DC to x-ray tubes.

3.  Potential difference defines, the work done on a unit
positive charge between two points thus moving it
from one point to the other.
 Unit measured : Volts
 Symbol : V
 1 volt of potential difference exists between two
points if one joule of work is performed in moving
one coulomb of positive charge from one point to the
other. I.e. V=joules/coulombs
 An example of potential difference in everyday life
takes shape in the battery.
 The battery creates a potential difference in the wire
due to its "electromotive force". This enables the
charge to travel from the battery to device.

4.  Definition: the potential difference between
the terminals of a source of electrical energy,
tends to give rise to an electric current.
 Unit: V (volts)
 Symbol : E or ℰ
 ℰ=W/q ( work / unit of charge)

5.  Definition: A measure of the difference in
electric potential between two points in
space, a material, or an electric circuit,
expressed in volts.
 Symbol: V
 To calculate Voltage we can use two
formulas. These are as follows;
1. Ohm’s law : states that voltage = current x
resistance (V = I x R )
2. Power law equation : states that voltage =
power / current (V=P/I)

6.  Definition: charge is one of the basic properties of the
elementary particles of matter giving rise to all electric and
magnetic forces and interactions.ie. It is a physical property
of matter that causes it to experience a force when near other
electrically charged matter.
 Symbol: Q
 Unit: coulombs ( c )
 A common example of electrical charge is lightning. Lightning
is formed when super charged particles in the air collectively
become attracted to the earths surface. The movement of
these particles is so violent that enormous amounts of light,
heat and sound energy are given off resulting in lightning

7.  Current is a flow of electric charge through a medium in a stated
time. This means that the bigger the quantity of the electric charge,
the stronger the electric current is.
 Symbol : I
 Unit: A ( ampere )
 Formula: I = Q/t =nqvA or I = U/R
 The amount of charge with respect to time, that is charge per time.

8.  Difference between current and charge is, A
charge is the build up of electricity where as
electrical current is the actual flow of the
charge
Charge Current

9.  An X-ray tube is a vacuum tube that produces
X-rays.
 In order to operate X-ray tubes, a DC voltage
of a few kilovolts to as much as 100 kV is
applied between the anodes and the cathode,
So that there are electrons being generated to
struck the atoms of the anode.

10.  Theseparticles will then pass
through the patient and….