) the change energy levels measured
across the load terminals.
.
Phasor phasor straight line, having definite length and direction, which rep-
resents scale the magnitude and direction quantity such cur-
rent, voltage impedance. the regulation to
be met ‘so far reasonably practicable’, then risks, cost, time, trouble
and difficulty can considered.
Power Power the rate doing work.d.
Pressure stress
Force
Area
N/m
)
2
Primary cell primary cell cannot recharged.
Potential difference The potential difference (p.
Relay relay electromagnetic switch operated solenoid.
Power
Work done
Time taken
W
)
Pressure stress Pressure stress measure the force per unit area.) defined the cosine the phase angle between the
current and voltage.
Rubber Rubber tough elastic substance made from the sap tropical plants.f.
Resistivity The resistivity (symbol the Greek letter ‘rho’) material defined as
the resistance sample unit length and unit cross-section.Glossary terms
381
Personal protective equipment PPE defined all equipment designed worn, held, protect
(PPE) against risk health and safety. This also called the volt drop terminal volt-
age, since emf and p.
Protective equipotential bonding This equipotential bonding for the purpose safety. Once the active chemicals are
exhausted, the cell must discarded.
Reasonably practicable absolute the requirement the regulation absolute, then that regulation must
be met regardless cost any other consideration.
Plastic plugs plastic plug made hollow plastic tube split half its length to
allow for expansion. Each size plastic plug colour-coded match a
wood screw size.d.
Polyvinylchloride (PVC) PVC used for cable insulation thermoplastic polymer.
PVC/SWA cable installations Steel wire armoured PVC insulated cables are now extensively used on
industrial installations and often laid cable tray.
Power factor Power factor (p.
Resistance any circuit, resistance defined opposition current flow. are both measured volts.
Risk assessments Risk assessments need suitable and sufficient, not perfect.
Risk risk the ‘likelihood’ harm actually being done
