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Evan Toh
May 90 min read
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Brightness of bulb - 100W vs 60W
Brightness of the filament bulb depends on power. The design of the filament is such that it uses tungsten (high resistivity), coil up (to increase the length) and thin tungsten filament (small cross-sectional area). These features are to let the tungsten filament achieve a certain amount of resistance, so that when current flows through, energy is transferred electrically to the internal (thermal) store of the filament, so that it is hot and the filament glow and gives out l
Evan Toh
Apr 181 min read
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Evan Toh
Mar 180 min read
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Evan Toh
Mar 180 min read
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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
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Various graphs of a simple pendulum and vertical oscillating object
As the reference height is at B, so above that reference height is considered positive, and below the reference height it is considered negative. Hence the height-time graph is as such. Consider a vertical oscillating object, similar to the simple pendulum, the middle is the fastest.
Evan Toh
Nov 5, 20251 min read
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How to make the image formed on the screen sharp?
To get a sharp image on the screen, there are various methods and concepts that you have learned and can be applied here. View the video for the explanation:
Evan Toh
Oct 29, 20251 min read
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Why charging your EV with a wall socket is not advisable?
There is a related question in Pure Physics 2021 P2 Q9, but slightly different. It asked about why home circuit of 230V is not suitable...
Evan Toh
Oct 11, 20251 min read
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Velocity-time graph of ball thrown up with air resistance - Part 2
Refer to the video below for the explanation. Related post: Velocity-time graph of ball released from rest with air resistance - Part 1...
Evan Toh
Sep 26, 20251 min read
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Velocity-time graph of ball released from rest with air resistance -Part 1
Refer to the video below to understand how to sketch the graph. For O-Level, we just need to focus on the general shape. 2024PP Paper 2...
Evan Toh
Sep 26, 20251 min read
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Evan Toh
Jun 8, 20250 min read
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Evan Toh
Jun 4, 20250 min read
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Evan Toh
Jun 4, 20250 min read
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Evan Toh
Jun 4, 20250 min read
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Evan Toh
Jun 4, 20250 min read
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Evan Toh
Apr 13, 20250 min read
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Evan Toh
Mar 19, 20250 min read
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Heating and Cooling Curves (updated)
Internal energy of a substance is the sum of kinetic energy and potential energy of the molecules. kinetic energy is directly...
Evan Toh
Feb 16, 20251 min read
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Orders of magnitude of sizes of atom, hair and Earth
In the syllabus, we are required to understand the orders of magntiude of various objects. Though we may no need to memorise the exact...
Evan Toh
Jan 10, 20251 min read
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FRHR Dab
Fleming's Right-Hand Rule is another useful rule for understanding electromagnetic induction. This rule helps us determine the direction...
Evan Toh
Nov 14, 20241 min read
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