A technical worker in construction and manufacturing industries is paid more than a skilled or semi-skilled worker because they have
Higher levels of knowledge and skills
Define Voltage
is the electric pressure or push from a power source
e.g water pump
V = I X R
What is the formula for ohm law?
PPE Means
Personal protective Equipment
Which of the following members of the building team carries the greatest level of responsibility on the construction site
Contractor, civil engineer, projector manager, trade foreman
Project manager
Define Current?
What is it measured in?
is the flow rate of electrons through a conductor
measured in amperes A
If voltage is 12 V and resistance is 4 ohm what is current?
I=3A
State two effects of an electric current in a circuit.
Lighting effect
Heating effect
magnetic effect
chemical effect
The role of civil and structural engineering is to produce buildings for
domestic use, the banking sector, industrial use , public use
Public use
What is Frequency?
What is it measured in?
is the number of cycles per second.
measured in Hz
If a circuit has a 3 A current and 6 ohm resistance, find the voltage
V= 18V
A potentiometer is
a variable resistor
A series circuit has a total resistance of 12 ohm and a current of 2 A. Find the supply
V=24V
What is resistivity?
is the property of a material that quantifies how strongly it resist the flow of electric current.
A resistor has 9V across it and passes 0.3A current. What is its resistance?
R= 30ohm
What is an insulator?
Name an example
Blocks the flow of electrons
Glass, rubber, wood
Why is series circuit not suitable for home wiring
If one device fails, the entire circuit is broken
What is temperature coefficient?
describes the relative change in a physical property when resistance changes.
state what happens to current if voltage increases but resistance stays the same
Current increases (directly proportional )
what is a conductor?
Give an example?
Allows the free flow of electrons
examples copper, aluminum