Are you a Form 2 student staring at a diagram of wires, bulbs, and batteries, wondering where the current goes? You aren't alone. The Electricity chapter is one of the most important—and sometimes confusing—topics in the Form 2 Science syllabus.
Whether you are preparing for your mid-year exams or just trying to finish your homework, this guide breaks down the "top" concepts you need to know to ace your F2 Science Electricity exercise.
Let’s switch on the power and get started!
Example 1: Why do bulbs dim when adding more bulbs in series?
Answer: Total resistance increases, so current decreases (Ohm’s Law). Lower current means less power to each bulb.
Example 2: Why are household appliances wired in parallel?
Answer: Each receives the full 240 V (or 120 V), and switching one off does not affect others.
Circle the best answer.
Which of the following is a conductor of electricity?
A) Rubber
B) Plastic
C) Copper
D) Wood f2 science electricity exercise top
In a simple series circuit with one bulb and one battery, if you add another bulb in series, the bulbs will:
A) Glow brighter
B) Glow dimmer
C) Stay the same
D) Not light up at all
The unit of electric current is:
A) Volt (V)
B) Ohm (Ω)
C) Ampere (A)
D) Watt (W)
What does a voltmeter measure?
A) Current
B) Potential difference
C) Resistance
D) Power
In a parallel circuit, if one bulb burns out, the other bulbs will:
A) All go out
B) Glow brighter
C) Stay lit
D) Explode
Which of the following correctly describes Ohm’s Law?
A) V = I + R
B) V = I × R
C) V = R / I
D) V = I – R
A circuit has a voltage of 12 V and a resistance of 4 Ω. The current is:
A) 48 A
B) 16 A
C) 8 A
D) 3 A ⚡ Mastering the Current: A Guide to F2
Which symbol represents a cell in a circuit diagram?
A) —o—
B) —∣∣—
C) —///—
D) —M—
The purpose of a switch in a circuit is to:
A) Increase current
B) Change resistance
C) Open or close the circuit
D) Measure voltage
If the resistance is constant and voltage doubles, current will:
A) Halve
B) Stay the same
C) Double
D) Become zero
Use Ohm’s Law (V = I × R) to solve.
(3 marks) A hair dryer draws 5 A of current when connected to a 120 V outlet. What is the resistance of the hair dryer?
(5 marks) A 6V battery is connected to two parallel resistors: 3Ω and 6Ω.
a) (2 marks) Calculate the total resistance of the parallel combination.
b) (3 marks) Calculate the total current supplied by the battery. Exercise Type 5: Short Answer & Reasoning Questions
Question Example:
A 12 V battery connects to two parallel resistors: 6 Ω and 3 Ω. Find:
a) Equivalent resistance
b) Total current
c) Current through each resistor
Solution:
a) ( \frac1R_p = \frac16 + \frac13 = \frac16 + \frac26 = \frac36 \Rightarrow R_p = 2 , \Omega )
b) ( I_\texttotal = \frac122 = 6 , \textA )
c) ( I_6\Omega = \frac126 = 2 , \textA, \quad I_3\Omega = \frac123 = 4 , \textA )
Key observation: Current splits but voltage across each branch = battery voltage.
Before diving into the exercises, let us diagnose the three biggest pain points:
The top exercise below is designed to fix these three problems.
