SPM Waves : Facts U Should Know!

Facts about Waves

1. Waves transfer energy without transfering the matter.
2. Transverse wave's particles vibrate perpendicular to the wave direction.
3. Longitudinal wave's particles vibrate parallel to the wave direction.
4. The amplitude of a wave determines its energy. Higher amplitude has greater energy.
5. Damping of wave causes decrease in amplitude & energy.
6. Waves' wavefront is always pependicular to the direction of the waves.
7. Waves undergo all of these phenomena; reflection, refraction, diffraction & interference.
8. Water,light & electromagnetic waves are transverse waves.
9. Coherent waves have same frequency & in phase.
10. As the frequency of a wave increases its energy increases and its wavelength decreases.
11. Shorter waves with higher frequencies have shorter periods.

Facts about Light Wave

1. Light is a transverse wave
2. Light slows down, bends toward the normal and has a shorter wavelength when it enters a higher refractive index(n).
3. Medium with higher refractive index has higher optical density.
4. At the critical angle a light wave will be refracted to 90 degrees.
5. Blue light has more energy,a shorter wavelength and a higher frequency than red light (remember- ROYGBIV).
6. Monochromatic light has one color, frequency & wavelength.

Facts about water waves

1. Water waves moves faster at deeper region. This change in speed causes refraction of water waves.
2. Water waves has longer wavelength at deeper region.
3. Deeper region is less dense than shallow region.
4. Water waves bended towards normal as it moves from deeper to shallow region.
5. After diffraction, water waves amplitude decrease thus its energy decrease as well.However its speed, wavelength & frequency remain constant.

Facts about sound waves

1. Sound is a longitudinal waves.
2. Sound is produced through vibration, thus compressing & stretching the surrounding air molecules.
3. Louder sound has bigger amplitude.
4. Sound with high pitch has higher frequency.
5. The sound that we hear is known as 'audio sound' that has freuency between 20-20khz.
6. Those sound below 20hz is known as infrasound. While sound with frequency beyond 20khz is known as ultrasonic.
7. Sound require medium to travel. It travels fastest in solid> liquid> gas.
8. Sound can't be heard in vacuum
9. Therefore..Starwars' sound effect in outer space is a myth :)

Forces & Motion: Facts You Should Know!!

SPM Physics :FAST Facts You Should Know About Chapter 2 Form 4!!
Compiled by cikgufizik @ www.physics4spm.com

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FAST Facts about Speed & Velocity

1. Speed, distance [d], time, and energy (joules) are scalar quantities.
2. Speed is rate of change of distance, i.e = distance/time
3. The gradient of distance-time graph is a speed.
4. Velocity, displacement [s], momentum, force and acceleration are vectors.
5. Velocity is the rate of change of displacement, i.e = displacement / time
6. The gradient of the displacement-time graph is also the velocity.

FAST Facts about Forces & Acceleration

1. Acceleration is the rate of change of velocity.
2. The gradient of the velocity-time graph is also the acceleration.
3. Zero acceleration also means either the object is at rest or moving at constant velocity.
4. Weight (in newtons) is mass x gravitational acceleration (w = mg). Mass is not weight!
5. Unbalanced forces will produce acceleration, i.e object not in equilibrium
6. Constant velocity and zero velocity means the net force is zero and the forces are in equilibrium
7. The equilibrium forces is equal in magnitude but opposite in direction to the resultant vector.

FAST Facts about Momentum

1. Momentum is a product of mass & velocity.
2. Momentum is conserved in all collision systems.
3. Total momentum before collision = total momentum after collision
4. Rate of change of momentum over time is an impulsive force. ( mv-mu) /t
5. Change in momentum is an impulse (mv-mu)

FAST Facts about POWER & ENERGY

1. Energy is a work done.
2. Energy is a scalar qty.
3. Energy can't be created or destroyed by human.
4. Energy can only be transformed.
5. Total energy dring the transformation is constant. (Total initial energy = Total final energy)
6. Gravitational potential energy increases as height increases.
7. Kinetic energy changes only if velocity changes.
8. Eleastic potential energy of the spring increases as the extension or compression of the spring increase.
9. The units for power are [joules/sec] or Watt (W).
10. Power is the rate of work done
11. 1 watt is 1 joule of work being done in 1 second.

Form 4 Post mortem

Dear all..

Welcome to the month of February , the month with shortest no.of days but lots of public holidays :) [ Hari Wilayah (1st Feb) ,chinese new yr(14-15 Feb) & maulidur rasul (26 Feb)]. This is the month where teachers gonna be strugling to cope with their lesson plan as scheduled. By the way, i'm not gonna discuss about the lesson plan.

I will start my discussion with a simple question to all SPM candidates:

How many hours did u spend to revise form 4 chapters in a week ???

If your aswer is NO & have done nothing on form 4 so far, i think u need to reorganise your study plan. The purpose i'm telling u this due to my students poor performance in their recent 'intervensi test' [.. valid for KL student only]

After having their results, most of them realised that they've forgotten most of the important physics facts in form4. I've been telling them so many times, if u dont have proper form4 revision plan.. u'll forget lots of things.

Ok some of them argued that their brilliant classmates dont need to revise them every week. Well i asked them back, ..Do u think they were telling u the truth??? Do u really know what these 'A' students are doin at home?? Anyway..ask your self again..Do your brain processor work as fast as their 'pentium dual core processor'??? If the answer is NO, then u better slap your face NOW, before its too late!

For this reason i'm asking for those who hardly pass their physics to at least consistently revise form4 topics in a week. For me, if u spend only an hour for form4 topics in a week wont be enough.WHy??..coz u have 3 physics papers to answer in SPM. Each paper will test u any form4 chapters.

For example in paper 3 section B, u will be given an option to design only one form4 experiment.

Let say U might have learned more than 15 experiments in form4. Out of all these experiments only 1 will come out in the exam...so the probability is roughly about 1 out of 15. None of us know which one will come out..Each experiment requires u to memorise the diagram, list of apparatus, procedure..and so on. ..I'm only talking about physics paper3, tak campur other papers as well...

On top of that..u have at least another 8 subjects plus form 5 topics to deal with. Btw,I think its time for u to do a post mortem on all form 4 chapters!!!

Otherwise, if u dont prepare from now...

Do u think u can understand & memorise all of those form4 topics just 3 months before 'trial' or 'SPM'???