PHYSICS EXAMINATIONS

1
PHYSICS EXAMINATIONS 2007

• Bruce Walsh

2
REMINDERS

• Calculators
• Study design and textbooks
• Examiners report
• VASS system
• SSMS
• Exam format - detailed studies

3
JUNE EXAMINATION
4
STATISTICS

• 6544 students
• Mean 99 55
• Std dev 41.5 23
• Number achieving 100 4

5
(No Transcript)
6
GENERAL COMMENTS

• Challenging
• Detailed studies
• Attempt ONE detailed study only
• Explanations address specific question.
  Diagrams
• Show working

7

• Converting units
• Calculations powers of 10
• - raising to power eg. R3
• - simple mathematics
• Care reading scale on axes
• Multiple choice questions
• Illegible writing

8
PROBLEM AREASMOTION

• Q2 Light lands directly below seat
• Q5 Determining ?p
• Q9, 10 In spring formulae x is extension not
  total length
• Q11 Total energy is constant

9

• Q12 Difficulty with ratios
• Q13 Mathematical difficulties with R3 and T2
• Q14,15 Treat horiz and vert components. Derived
  equations caused confusion

10
ELECTRONICS PHOTONICS

• Q1,2 Improving, but still difficult for students
• Q3 Few provided a clear answer
• Q9 Explanations unclear
• Q10,11 Intensity of light cannot go below zero

11
RELATIVITY

• Q2 Many unable to determine speed of sound
• Q8 Determining appropriate frame of reference

12
MATERIALS STRUCTURES

• Q2 Torques
• Q4 Locating point of tension
• Q8 Work Area of graph x Volume. Many forgot
  volume
• Q10 Torque or triangle of forces or resolution of
  forces

13
FURTHER ELECTRONICS

• Q5 Time constant 63 change
• 10 Increased I ? increased voltage drop OR
  Decreased load ? decreased ? and increased ripple
• Q11 Regulator, increase transformer output,
  increase capacitor

14
NOVEMBER EXAMINATION
15
STATISTICS

• 6392 students
• Mean 110 61
• Std dev 43 24
• Number achieving 100 14

16
(No Transcript)
17
GENERAL COMMENTS

• Accessible paper
• Detailed studies
• Illegible writing
• Explanations must address specific question

18

• Explanations one mark per point
• Show working
• Unit conversions, eg. cm2 to m2
• Powers of 10 calculations
• Transformation of simple equations.

19

• Direction of current flow
• Diffraction Light Matter c.f. Sound
• Diffraction patterns gradual change as ?/w
  ratio varies

20
PROBLEM AREASELECTRIC POWER

• Q1,2 Sketching magnetic fields.
• Q11 Series circuit ideas
• Q12 More power consumed than supplied
• Q15 Explain application of Lenzs law

21
LIGHT and MATTER

• Q5, 6 Diffraction patterns
• Q9 Not interference effect
• Q10, 11 Behaviour of bound and free electrons

22
SYNCHROTRON

• Q4 Application of right hand rule
• Q11 Explanations poor

23
PHOTONICS

• Q6 Snells law
• Q7, 8 Relate effect to speed variations
• Q11 Internal reflection gradual change in
  amount

24
SOUND

• Q4 Resonance will be louder
• Q7 Relate graph to frequency range of human voice