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Background

An Aided Secondary School in Tuen Mun

An EMI School

S4-6 Elective Subjects in 2009-2012 (1st Cohort)

A B C D E

Chinese History

BAFS Economics Physics Physics

History / Chinese Literature / BAFS / Integrated Science

Chemistry Chemistry

Geography / ICT / Visual Arts / Economics / BAFS / Biology

Biology

OLE M2 M2

S4-6 Elective Subjects in 2012-2015 (4th Cohort)

A B C D E F

Chinese History / BAFS / Economics / Integrated Science/ Physics (Class E only)

Biology

History / Chinese Literature / Economics / BAFS / Chemistry Physics

Geography / ICT / VA / Economics / BAFS / Biology Chemistry

OLE M1 M2 M2

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Some NSS Math Learning Units related to Physics

Core

1.4 solve quadratic equations by the quadratic formula (S4 1st term)

2.3 understand the features of the graphs of quadratic functions (S4 1st term)

3.3 understand the definition and properties of logarithms (including the change of base) (S4 1st

term)

6.2 understand the graphs of direct and inverse variations (S4 2nd term / S5 1st term)

12.1 understand the equation of a straight line (S4 2nd term)

13.1 understand the functions sine, cosine and tangent, and their graphs and properties, including maximum and minimum values and periodicity (S5 2nd term)

M2

7. Differentiation (S4 2nd term)

15. Introduction to vectors (S6)

Some common practices in physics

Significant figures

Scientific notation

S.I. units

Use of calculators

Use of rulers

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Vectors

Mechanics

Displacement

Force

Moment

Work done

Electricity & Magnetism

E-field

B-field

Addition of forces

tip-to-tail method

F1

F2

F1 F2+

Addition of forces

parallelogram of forces

F1

F2F1 F2+

Resolution of forces

Fx

Fy F

x

y

= F cos

= F sin

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The concept of Unit Vector

HKCEE 2008 P1 Q9

Candidates were not familiar with the use of vector diagram when finding theresultant force. Only the more able candidates could draw the vector diagramcorrectly with the resultant T in the upward vertical direction.

Some wrongly took Figure 15 in the question paper as a vector diagram drawn to scale and wrongly copied T2 (both in magnitude and direction) ontoFigure 16.

HKCEE 2009 P2 Q7

Ans: A (78%)

HKCEE 2009 P2 Q29

Ans: C (57%)

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HKCEE 2005 P2 Q32

Ans: D (52%)

HKCEE 1999 P2 Q5

Ans: C

HKCEE 2002 P2 Q9

Ans: A (17%)

Equation of a straight line

y = mx + c

v = u + at

Slope = acceleration

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v-t graphs

y = mx + c

v = u + att

v

t

v

t

v

t

v

HKCEE 2000 P2 Q4

Ans: B

HKCEE 2000 P2 Q4

Ans: B

HKCEE 2000 P2 Q4

Ans: B

Part (a)(i) was well answered. In (a)(ii)(iii), some candidates failed to sketch the variation of the speed of Train A correctly and thereforethey were unable to determine the two trains’ separation using the area under the graph.

HKDSE 2012 P1B Q4

HKDSE 2012 P1A Q7

Ans: A (63%)

HKDSE 2012 P1A Q7

Ans: A (63%)

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HKCEE 2004 P2 Q7

Ans: D (51%)

2

21 ats

asv 22

atv HKCEE 2004 P2 Q7

Ans: D (51%)

2

21 mvKE

HKCEE 2000 P2 Q10

Ans: C

Ans: E

HKCEE 2000 P2 Q9

HKDSE 2012 P1A Q11

Ans: A (58%)

)(1 fFm

a

fFma

Equation of a straight line

x + y = constant

KE + PE = constant

fvu111

x

y

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HKCEE 2002 P2 Q8

Ans: C (48%)

HKDSE Practice Paper 1A Q21

Ans: D (51%)

Direct and Inverse Variations

Newton’s Second Law, F = ma

Boyle’s Law, pV = constant

Centripetal force, T = m2L

Newton’s Second Law

Plot a graph of acceleration a against net force F.

a F (const m)

Plot a graph of acceleration a against1/m.

a 1/m (const F)

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Boyle’s Law

Plot a graph of p against 1/V at constant T

MslottedweightsM

papermarker

papermarker

rubberbung

glass tube

1.5 m length of nylon thread

glass tube

mL

rubberbung

Centripetal force

T = m2L

Centripetal force

T = m2L

Plot a suitable graph to find the relation between and T.

2 T (const m, L)

Plot a suitable graph to find the relation between and L.

2 1/L (const m, T)

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HKCEE 2006 P2 Q17

Ans: A (47%)

HKCEE 2006 P2 Q5

Ans: C (65%)

t

v

HKCEE 2008 P2 Q8

Ans: B (49%)

22

22

21

)(21

21

tma

atmmv

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HKCEE 2009 P2 Q6

Ans: B (36%)

FatFvPatv

HKCEE 2007 P2 Q4

Ans: D (35%)

mas

asm

mvKE

)2(2121 2

smgmgHsHmgPE

)sin()sin(

singa

HKCEE 2010 P2 Q7

Ans: A (45%)

2

21 mvKE

negative. is where222

aasuv

Some Other Math Skills

Plotting graphs

Best fit straight line

Finding the slope of a straight line graph