§-Past paper

VICPhysics2025

VCE Physics 2025

Walkthrough of the 2025 VCE physics exam: what it assessed, strategy tips, and the common errors flagged in the official marker report.

Marks: 130
Time: 150 min
Authority: VCAA
Updated: 2026-05-29

Open the official PDF ->Official marking notes

What this paper assessed

The VCE Physics Units 3 and 4 examination (130 marks, 150 minutes) assesses the VCAA study design across:

Unit 3 - How do fields explain motion and electricity: gravitational, electric and magnetic fields and their similarities; motion in fields (projectile motion, circular and satellite motion); the motor effect and DC motors; and electromagnetic induction, generators, transformers and the transmission of electrical power.
Unit 4 - How have creative ideas and investigation revolutionised thinking: waves (interference, diffraction, the wave model of light); the photoelectric effect and the particle model; matter waves and the de Broglie wavelength; and Einstein's special relativity (time dilation, length contraction, mass-energy equivalence $E=mc^2$ ).

You are given the VCAA formula sheet. The exam includes multiple choice and short/extended answer, with several data-analysis items requiring you to read a graph, apply a relationship, and comment on the model's limitations. It rewards stating each equation with defined variables, carrying units, and appropriate significant figures.

Structure and timing

The paper is 130 marks in 150 minutes (plus 15 minutes reading time) - about 1.15 minutes per mark, so pace is brisk.

Multiple choice / short items: about 1 minute per mark to bank time.
Extended-response and data-analysis items: the remaining time at ~1.2 min per mark, with multi-step calculations getting a moment to sequence.

Use the 15 minutes reading time to flag the heaviest calculation (often field/motion or transformer power) and the graph-analysis items. Reserve ~10 minutes at the end to check units and that each reasoning item names the law applied.

Worked practice questions (exam-style)

Worked example

Question 1 (5 marks): A satellite of mass $m$ orbits a planet of mass $M = 6.0\times10^{24}\ \text{kg}$ at radius $r = 8.0\times10^6\ \text{m}$ . Using $G = 6.67\times10^{-11}\ \text{N m}^2\text{kg}^{-2}$ , find the orbital period.

Gravity is the only force acting on the satellite, and it must supply all of the centripetal acceleration. Setting the two force expressions equal and eliminating the satellite mass gives the period formula.

Step 1: Equate gravitational and centripetal forces

For a circular orbit with centripetal acceleration $a = \dfrac{4\pi^2 r}{T^2}$ :

\frac{GMm}{r^2} = \frac{4\pi^2 m r}{T^2}.

The satellite mass $m$ cancels from both sides, giving:

T^2 = \frac{4\pi^2 r^3}{GM} \quad\Rightarrow\quad T = 2\pi\sqrt{\frac{r^3}{GM}}.

Step 2: Calculate the intermediate quantities

Cube the orbital radius: $r^3 = (8.0\times10^6)^3 = 5.12\times10^{20}\ \text{m}^3$ . Compute the gravitational parameter: $GM = (6.67\times10^{-11})(6.0\times10^{24}) = 4.00\times10^{14}$ .

Step 3: Substitute and evaluate

T = 2\pi\sqrt{\frac{5.12\times10^{20}}{4.00\times10^{14}}} = 2\pi\sqrt{1.28\times10^{6}} = 2\pi \times 1131 = 7.1\times10^{3}\ \text{s}.

Final answer: the orbital period is $7.1\times10^3\ \text{s}$ (approximately 2.0 hours).

Worked example

Question 2 (5 marks): An ideal transformer steps $240\ \text{V}$ down to $12\ \text{V}$ . The primary coil has $1000$ turns. (a) Find the number of secondary turns. (b) If the secondary delivers $2.0\ \text{A}$ , find the primary current.

(a) For an ideal transformer, $\dfrac{V_p}{V_s} = \dfrac{N_p}{N_s}$ :

N_s = N_p\cdot\frac{V_s}{V_p} = 1000 \times \frac{12}{240} = 50\ \text{turns}.

(b) An ideal transformer conserves power, $V_pI_p = V_sI_s$ :

I_p = \frac{V_sI_s}{V_p} = \frac{12 \times 2.0}{240} = 0.10\ \text{A}.

So the primary draws

0.10\ \text{A}

. The conceptual mark: a step-down transformer reduces voltage but increases current on the low-voltage side, with power conserved (in the ideal case). EMF here arises from the changing flux linking the secondary, an application of Faraday's law.

Worked example

Question 3 (4 marks): In a photoelectric experiment, the stopping voltage is measured for several frequencies of incident light, and a graph of stopping voltage against frequency is a straight line. (a) State what the gradient represents. (b) Explain how this experiment supports the particle model of light.

(a) From $eV_0 = hf - \phi$ , rearranged as $V_0 = \dfrac{h}{e}f - \dfrac{\phi}{e}$ , the graph of $V_0$ against $f$ is linear with gradient $\dfrac{h}{e}$ (Planck's constant divided by the electronic charge) and a frequency-axis intercept at the threshold frequency.

(b) The experiment supports the particle (photon) model because emission depends on the frequency of light, not its intensity: below a threshold frequency no electrons are emitted regardless of how bright the light is, and the maximum kinetic energy rises linearly with frequency. The wave model predicts that any frequency, given enough intensity and time, should eject electrons - which is not observed. A photon of energy $hf$ delivering quantised energy to a single electron explains the result, which is the reasoning the marks require.

Common errors students made

The VCAA examiners' report patterns flagged missing units, mixing scalar and vector quantities, treating projectile motion as one-dimensional, and forgetting that induced EMF depends on the rate of change of flux rather than the flux itself. Further recurring traps:

Numbers without stated equations or defined variables, forfeiting method marks.
Errors in powers of ten when cubing $r$ or handling $GM$ in orbital problems.
Confusing step-up and step-down behaviour in transformers, or forgetting that current changes inversely to voltage.
Relativity answers that omit the frame - state which observer measures proper time/length versus the dilated/contracted value.
Describing the photoelectric or interference experiment without stating which model (particle or wave) it supports and why.

How to use this paper

Sit the paper in 150 minutes under exam conditions. Mark strictly against the official VCAA examiners' report and answers at the links in the frontmatter, noting where method marks are awarded. Rebuild every calculation that lost more than half its marks, writing the named equation and defining each variable before substituting. For graph items, practise interpreting gradient and intercept and stating their physical meaning. Keep an error log sorted by topic (orbits, transformers, induction, photoelectric, relativity) and re-test that class next session.

Use this paper well

Sit the paper under exam conditions (150 minutes, 130 marks).
Mark yourself against the official VCAA marking notes.
Compare against the Physics hub to find the syllabus dot points this paper tested.

What this paper assessed

Structure and timing

Worked practice questions (exam-style)

Common errors students made

How to use this paper

Use this paper well

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