Physics Tips 2008(SPM Final Revision)

Physics Tips SPM 2008
From: Mr.Nava.S Desk

1.Measurement- Vernier Calipers/Micrometer

2.Impulsive force/Impulse-Try SBP questions (egg or watermelon drops from a table/2 objects collide from different directions)

3.Gas Law(Boyle’s/Charles) & Pressure in Liquid – Try questions on air bubble/Load on piston/Gas pressure related to a barometer

4.Hooke’s Law – pls know that area under this graph gives u work done=elastic potential energy

5.Bernoulli Principle – anything that in shape of aerofoil follows this law eg: curtain /tent

6.Archimedes Principle – Try questions involving boat and hot air balloon
7.Heat(SHC & Latent Heat)/Thermal Equilibrium

8.Snell’s Exp to determine value of critical angle using semi-circular glass block

9.Work,Energy,Power – Try question on Conservations of energy especially K.E and P.E

10.Youngs Exp.- both light and sound/ speed or water waves interference(nodal&antinodal)

11.Free Fall exp.

12.Convex Lens Magnification & Microscope/ Projector

13.Ohm’s Law – Learn simple calculations/gradient of graph V-R/Constant wire length and – resistance/ohmic and non ohmic conductor

14.Equilbrium of forces – car on slope/ anything tied to a string
15. Faraday/Lenz law/Motor – turning effect(Fleming Left Hand Rule)/relay circuit

16.Radioactive – chain reaction/simple calculations E=mc2/equations/half life calculation/nuclear reactor

17.Transistor exp. / Graph of Ib and Ic

18.Logic gates – don’t be sad u got to know all the gates before u can even try this !

If u have more time try doin questions on friction compensated trolley on a slope attached to ticker timer + kinematic calculations(car brakes on a rainy day) and Pascal principle ok !
Good Luck and Have A Great Day !

Remember Your Facts "Right"!

Good Luck !

Good luck and all the best to all those sitting for SPM on tuesday.
May god bless all of u.
Be confident and be focused when answering questions.

Biar besemangat bila menjawab soalan k.
Cheers :)

Answer Q18

Answer Q17

Answer Q16

Answer Q15

Answer Q14

Answer Q13

Answer Q12

Answer Q11

Answer Q10

Answer Q9

Answer Q8

Answer Q7

Answer Q5

Answer Q4

19thOCT Seminar Answers

Hi guys ill be updating the answers for the Seminar Sains Perdana conducted on the 19th Oct.
If there is any missing answers pls let me know by leaving comment on the comment box below

Wishing Stars !

Everyone born on this earth is a star. You need to know your talent. Don't you stop until you find it.
Have a great day.

Answer : Question 38

Answer : Question 37

Answer : Question 36

Answer : Question 35.1

Answer : Question 35

Answer : Question 33.1

Answer : Question 33

Answer : Question 32

Answer : Question 31

Answer : Question 30

Answer : Question 29

Answer : Question 28

Answer 26.2

Answer : Question 26.1

Click On The Image

Some answers are small. Hmmm i'm just learning to scan:)
Click on the image and u can the the answer really big okay !

Answer : Question 26

Question 26(missing diagram 4.3)

c)continuation ......the missing diagram 4.3

Answer : Question 25(cont)

Answer : Question 25

Light can be reflected, refracted or diffracted

Answer : Question 22

Hope all of u remember The "Gas Laws" Boyle's / Charle's / Pressure

Answer : Question 21(cont.)

Answer : Question 21

Answer : Question 19

Question on Heat Chapter

Answer : Question 17(cont.)

Answer : Question 17

This question is on Archimedes Principle

Definition : When an object is immersed partially or fully in a liquid it will experience an upthrust force(bouyant force) which is equal to the displaced liquid.

Answer : Question 15

This questions it about Bernoulli's Principle

Definition : When the velocity of a fluid is high it creates a zone with low pressure(layman sentence)

Hello Again Guys!

Hi was i thinking...and thinking and i felt so guilty...and i know i promised all the answers next tuesday but i then i tought its long so i decided to upload it now. Hope it helps. Any feedback,leave it on the comment box or mail me k (gns@email2me.net)

Mr.Nava.S

Hi I am Back !

Hello guys must be wondering where i went missing. No worries. Had lots and lots of stuff to do and was away quite long i guess. My sincere apology for that. Look out for the complete answers from next Tuesday(14/10/08). Cheers and be cool.Thanks for your patience.

Mr.Nava.S

Physics Tips/KL

Hi guys....there is some physics tips for KL students...i think its from gombak...got it from a student
Hope it could help ......looks genuine:)

1)velocity-time graph
2)Bernoulli Principle
3)Pressure Law
4)Convex lens
5)Refraction (water)
6)Archimedes Principle
7)Transistor(Auto Switch)

Hey don't depend so much on tips until u don't study.
Good Luck

Tips for Trial/Physics

Dear selangor students...i'll get some tips for monday exam
Ill update on friday evening

Tip of the Day

Link this two principle : Archimedes Principle and Principle of Equilibrium of Forces

Answer : When an object is floating or hanging in a liquid the total force upwards and total force downwards is the same.

so if an object is floating :
bouyancy force = weight of the object

and if its hanging on a spring balance:
bouyancy force + tension on the spring = weight of the object

Personal Message from Mr.Nava.S

Hi everyone i hope all of you have started your revision. Hope you use this school holiday opportunity well to accelerate your revision. For those waiting for the seminar answer i'm very sorry i'm not around to upload the balance answers. I promise ill do it just after the school holidays when i return.
Have a great holiday and have fun studying. Cheers.

Mr.Nava.S

Discussion 1 - Refraction of light

Diagram 1




Diagram 2

Discussion

All the questions is about Snell’s Law

Remember an important point when applying the formulae

n = sin i/ sinr

sin i = the value must be taken from air even if the ray is coming it coming from a medium

sin r = value from medium

Can you tell which is the incident angle, i and the refraction angle, r when light travels from glass to air ?

refering to diagram 1

Most of us think that the a is the incident angle, i ….its not wrong to think like that but if we apply the a value as sin i then ..lets see what’s happens to the index value(n)

n=sin 30/sin 40 =0.78

its less than 1… vice versa…if I let the ray in as in diagram 2 then it will go back the same way(from air to glass with same angle) . Agree ?

so in this case…b will be the incident angle, i …so

n = sin 40/sin 30 =1.29

so which value is right ?

index value should always be more than 1 for a medium

in this case the value 1.5 is the correct one

so to avoid confusion between incident angle and refraction angle….no worries

always assume the angle in the air is the incident

from this ,

n = sin i(air)/sin r(medium) ……no matter where the ray coming from….

Answer : Question 23&24

Question 23

i. a) r = 19^◦

b) n = 1.54 …………no unit for refractive index

ii. n = 1.40

Question 24

a) c = 24.6^◦

b) n = 1/sin c = 2.4

Answer : Question 32

Answer : Question 32 ( Interference)

a) Alternating loud and soft sound

b) * coherent source provides – constant phase difference when the two waves

interfere

*the same kind of interference, whether constructive/destructive interference will

occur at the same place all the time

*therefore the interference pattern of alternating loud and soft sound can be heard

c) ax = λD

λ = ax/D

= 0.6 x 2.4 / 3

= 0.48 m

Answer : Question 27

Answer : Question 27

a) i) optical fibre is denser than air, ray is refracted towards normal

ii) Total internal reflection(T.I.R) occur , where angle of critical more than critical angle

b) draw a ray going away from normal at B

c)
* endoscope
* cables for transmission of telephone signals…you broadband also uses this

Answer :Question 16

Answer : Question 16( Archimedes Principle)

a) i. The block rises to the surface of water

ii. The block rises to the surface of water because the upthrus(buoyant force)t on the block is greater than the weight of the block

b) The block rises to the surface of water.

c) i. Volume of the block = m/p

= 0.18/900

= 0.0002 m³

Upthrust = pvg

= 0.0002 x 1200 x 10

= 2.4 N

Use Principle of Equilibrium of Forces to answer this part(Total Force Top = Total Force Down)

Weight of load + Weight of block = Upthrust

So, Weight of load = Upthrust - Weight of block [ w=mg…so w= 0.18 x 10 = 1.8]

= 2.4 – ( 1.8)

= 0.6 N

ii. The block will immerse deeper in the liquid.

SEMINAR on 20th JULY 2008 !

Hi students.... we are having another session of Seminar on 20th July 2008. We'll cover all the topics covered in the first session. For those of you who feel that your classmates or friends can benefit from this seminar please pass the good news. It is good to share knowledge.

The number to call for details are :
Mr Chandran : 016 - 2960642 / Mr Devan : 016 - 338 2506


Thanks and regards

Management
Maha Edu & GnS

Answer : Question 10

Question 10

a) i) Both the coin and feather fall due to the gravitational pull. In the lab, when they move through the air, the air resists against their motion. The air resistance depends on the shape of the body and velocity of the body. The feather has greater surface area than the coin. Hence the feather experiences greater air resistance and its acceleration decreases.

There is no air in the vacuum cylinder. Thus two objects move down without air

resistance and reach the bottom of the cylinder at the same time.

ii) Parachute-----payung terjun

b) i) arrange data :

m1 = 200kg, u=12m/s

m2 = 300kg, v= ?? ( tak tahu)

this is an …..inelastic collision…

m1u1 x m2u2 = (m1+m2)v………hey u2=0 since its not moving

200 x 12 = (200+3000)v

v = 0.75 m/s

ii) Loss of K.E = Work done against friction

Loss of K.E = ½ mv² = ½ x 3200 x 0.75² = 900 J .....all the K.E used to move the stomp

Work done = force(friction) x distance

900 = f x 0.2 …………..must change cm to m

f = 4500 N

Answer : Question 6

Answer : Question 6

a) i) Momentum is the product of mass and velocity of the object

ii) The plasticine ball is flatter on wood than the plasticine on the sponge

There is no change on the surface of the wood but the surface of the sponge is dented by the palsticine ball. The time of impact on hard wood is shorter that that on the sponge. Hence the impulsive force on the wood is greater than on the sponge since impulsive force is the rate of change of momentum.

b) Before the plasticine ball is released from a height, it possesses G.P.E(gravitational potential energy). According to the principle of conservation of energy, when it is released, G.P.E is converted to K.E(kinetic energy). When it hits the wood or sponge, the K.E changes to sound energy and heat energy due to frictional force between the ball and the surface.

c) i)1. Satellite is made of materials with high melting point so that it is not easily melted when it reaches a high temperature

2. Satellite is designed to have an aerofoil shape which gradually tapers towards the end to decrease the air resistance.

3. Satellite is sheltered (protected) with insulators to prevent heat from entering.

ii) 1. Satellite is made of materials of low density to reduce the impulsive force on landing.

2. Satellite is made of composite material which is light, hard and strong so that it is not easily broken up on landing.-----you can use this answer for other questions as well

3. Satellite is attached with a parachute so that is descends slowly and decrease its velocity on landing.

SEMINAR SAINS SKOR A SPM

I would like to congratulate all those who attended the SKOR A SPM SEMINAR(SEMINAR SAINS PERDANA) on the 6th of July 2008 at Universiti Malaya !

Wish all of you the very best in your exams !

Please do mail me if you need any assistance and i will do my best to help you.

Mr.Nava.S

Skor A Seminar at UM on 6th July 08 !

We had a success in our seminar for Physics and Chemistry in UM. For all the students who came, I know you would have had a great time and most importantly gained a lot of insights in the subjects...

We here will try to guide you guys and gals when you face difficulty in understanding the subject. But... more importantly make full use of the notes, mind maps and explanation given in the seminar.

Due to good response and request we'll be having another seminar session on the 20th July 2008 at the same place covering the same topics. If you feel that your friends can do better in their exams by attending, please inform them.

The number to call for booking of place is as follows :-

016-338 2506 Mr Devan
016 -2960642 Mr Chandran

Physics Made Easy

I will start posting my physics made easy methods starting 7th July 2008 !
Look forward for some easy approach and question solving methods !