In general, assuming temperature of a conductor is constant, the resistance of a conductor is affected by
1) length (L) – [L increases, R increases]
2) cross-sectional area (A) – [A increases, R decreases]
3) resistivity (p) = [p increases, R increases]
As R is directly proportional to L and p, and is inversely proportional to A,
R = pL/A
There are times when using the formula is more appropriate.
Centre of gravity (CG) of an object is an imaginary point where the entire weight if the object seems to act.
In Singapore, we use the 3-pin wall socket 240 V. In general, it is more convenient if the plug of appliance is 3-pin. But certain appliances we bought online may not be, just like the fan shown in the video below. It has 2 pins, i.e. a live wire and a neutral wire. No earth wire is present as the outer casing is made of electrical insulator, plastic.
Take a look at the video, and you can easily convert the 2=pin to 3-pin plug.
Below are the questions.
2003PPq1q7 (0 min to 2.42 min) Ans: Option A
2023PPp1q4 (2.47 min 3.54 min) Ans: Option C
2018PPp1q2 (3.45 min to 6.22 min) Ans: Option D
2011PPp1q6, 2016PPp1q6 (6.22 min) Ans: Option A
Below are some examples of questions that involve finding the resultant force due to two or three forces.
2010PPp1q2 similar to 2002PPp1q7 (0s to 3.02 min) Ans: Option D and D respectively
2005PPp1q10, 2012SPp1q1, 2018PPp1q2 (4.25 min to 6.40 min) ANs: Option A
2014PPp1q8 (6.40 min to 7.48 min) Ans: Option B
2019PPp1q2 (7.48 min to 8.22 min) Ans: Option B
2020PPq1q3 (8.22 min to end) Ans: Option B
In the lab, usually we use these two types of voltmeter. One with a range of 0 to 3 V and the other with a range of 0 to 5 V.
Watch the video to learn how to read the respective voltmeter and how to record the reading.
Evan's Space 