N-Level Technical and Vocational Skills 2

Question 1

What is the difference between AC and DC electricity?

Accepted Answer

AC (alternating current) periodically reverses direction; DC (direct current) flows in one direction only

Answer

AC (mains electricity in Singapore — 230V, 50Hz) alternates direction. DC (batteries, electronic devices) flows in one constant direction. Most household appliances use AC; electronics convert it to DC internally.

Question 2

What does a fuse do in an electrical circuit?

Accepted Answer

Protects the circuit by melting and breaking the circuit if the current exceeds the safe rating

Answer

A fuse is a safety device containing a thin wire that melts and breaks the circuit if the current exceeds its rated value, preventing damage to equipment and reducing fire risk.

Question 3

What is the function of a resistor in an electronic circuit?

Accepted Answer

To limit or control the flow of electric current

Answer

A resistor limits current flow in a circuit. By Ohm's Law (V = IR), adding resistance reduces current for a given voltage, protecting sensitive components from too much current.

Question 4

What is 'Computer-Aided Design' (CAD)?

Accepted Answer

Using computer software to create, modify, and analyse design drawings — allowing precise, editable technical drawings

Answer

CAD software (e.g., AutoCAD, SolidWorks) allows designers and engineers to create precise 2D and 3D digital drawings that can be easily modified, shared, and used for manufacturing.

Question 5

In a food preparation environment, what does HACCP stand for and why is it important?

Accepted Answer

Hazard Analysis and Critical Control Points — a food safety system identifying risks in food production to prevent contamination

Answer

HACCP is a systematic food safety approach that identifies, evaluates, and controls biological, chemical, and physical hazards at critical points in food production to prevent foodborne illness.

GCE N-Level Practice Test

GCE N-Level Practice Test

N-Level Technical and Vocational Skills 2