Understanding Parallel Circuits: Calculating Resistance
“Is this office safe or unsafe? Why?”
2
minute
00
second
Lesson duration is: 30 minItems in this lesson
“Is this office safe or unsafe? Why?”
2
minute
00
second
Objective
What do you already know about series and parallel circuits
2
minute
00
second
Which picture shows a working circuit?
A
B
40
second
Answer A
Answer B
If one bulb breaks, do all bulbs go off? Yes or No?
40
second
YES
NO
Think, pair and share
“Do homes, offices, and colleges use series or parallel circuits? Why?”
Efficiency
Control
Safety
2
minute
00
second
Standards and Legislation in Electronics
Environmental Laws
WEEE → recycling electronics
RoHS → restricts hazardous materials
Key Legislation
Electricity at Work Regulations (1989) → safe use of electrical systems
Health & Safety at Work Act (1974) → protects users and workers
Low Voltage Directive → safe electrical equipment
Key Standards
BS / IEC → design & testing rules
CE / UKCA marking → legal compliance
IP ratings → protection from dust/water
Law: You must stop at a red light 🚦
Legislation: The government decided and created that traffic rule 🏛️
Standard: It’s best practice to check both sides before crossing 🛑
Standards, Safety & Application
Why Standards Matter
Ensure safety (prevent shock & fire)
Improve reliability and performance
Ensure compatibility
Meet legal requirements
Safe Testing Practices
Turn off power before changes
Use correct tools
Check voltage/current limits
Avoid short circuits
Follow risk assessment
Why It Matters
Without standards → danger, damage, legal issues
With standards → safe, reliable, legal circuits
Visualising with Circuit Software
You can use software like Tinkercad Circuits, Falstad Circuit Simulator, Multisim to build and test electronic circuits virtually.
Risk Assessment sheet
Individually in Silence
Complete a risk assessment sheet on building and testing electronic circuit
3
minute
00
second
Are you confident in building simple series and parallel cicuit?
Can you identify whether a circuit is series or parallel in real-life examples, and explain why that type of circuit is used?
Ask 1 question about something you haven't quite understood yet.
Reflection time
