top of page


Which bulb X or Y is brighter, and which has higher resistance?
There are factors that affect resistance of the filament (conductor): length cross-sectional area Resistivity For our syllabus, brightness of the bulb depends on power. The higher the power, the brighter the bulb. e.g. a 100 W bulb is brighter than a 60 W bulb, View the video to understand the concepts better Video
Evan Toh
Mar 41 min read


I-V graphs of various components
For Science Physics, you just need to the I-V graphs of ohmic conductor e.g fixed resistor and non-ohmic conductor e.g. filament bulb/lamp. For Pure Physics, all the 4 components are needed.
Evan Toh
Feb 271 min read


Which statement describes an electrical source of 5V?
Answer: Option B Emf is the work done (energy needed) to carry a unit charge (1C) through the whole complete circuit. By definition, it...
Evan Toh
Jul 6, 20251 min read


Evan Toh
Apr 13, 20250 min read


Evan Toh
Mar 19, 20250 min read


Evan Toh
Mar 2, 20250 min read


What is the resistance of Y when its length is doubled and diameter three times larger? 2018PPp1q31
When question states that radius or diameter is increased by 3 times, that note that cross-sectional area does not increase by 3 times....
Evan Toh
Nov 4, 20241 min read


2007PPp1q28 2019PPp1q33 - Which V-I readings are for torch lamp?
2019PPP1Q33 Ans: Option B 2007PPP1Q28 Ans: Option B Torch lamp or bulb is a non-ohmic conductor . The V-I graph has an increasing...
Evan Toh
Oct 25, 20241 min read


2024 Specimen Paper 6091 P1 Q30 Filament bulb graphs
When comes to filament lamp, the non-ohmic characteristic properties comes to mind. But for this quesitons, you have to understand that...
Evan Toh
Oct 23, 20241 min read


2010SPP2Q12 Fuel gauge using variable resistor
Solutions: As the fuel level drops, the float which stays on the fuel surface will descend. The rod which is attached to the float will...
Evan Toh
Oct 22, 20241 min read


When a thermistor is connected in series with a fixed resistor, how to explain the p.d. varies as resistance temperature changes?
When two components are connected in series, where one is a fixed resistor and the resistance of the other can vary (e.g. thermistor,...
Evan Toh
Oct 21, 20241 min read


Factors that affect the resistance of a conductor
In general, assuming temperature of a conductor is constant, the resistance of a conductor is affected by 1) length (L) – [L increases, R...
Evan Toh
Oct 21, 20241 min read


2021PPp1q36 DC circuit, which circuit has a potential difference between P and Q
Do you understand why there is a potential difference between P and Q? What if you are to find the potential difference between P and Q?...
Evan Toh
Oct 15, 20241 min read


2012PPp2q07 - Find the p.d. across A and C
Instead of the usual finding of potential difference across a component, in this question, you are required to find the p.d. across two...
Evan Toh
Oct 15, 20241 min read


Evan Toh
Sep 1, 20240 min read


Evan Toh
Sep 1, 20240 min read


Evan Toh
Sep 1, 20240 min read


Evan Toh
Sep 1, 20240 min read


Finding total effective resistance
For resistors connected in series, the total resistance is the sum of all resistance. Re = R1 + R2 + R3 For resistors in parallel, the...
Evan Toh
Jan 1, 20241 min read


Evan Toh
Jan 1, 20240 min read
bottom of page
.png)