VCAA Physics How is scientific inquiry used to investigate fields, motion or light?
5 sample questions with marking guides and sample answers
The experimental uncertainty of a measurement is best understood as
an estimate of the validity of the data.
a mistake in the experimental method used.
a mistake in the recording of a measurement.
an estimate of the maximum likely difference between the measurement and the true value.
Reveal Answer
an estimate of the validity of the data.
Validity refers to how well an experiment measures what it intends to measure, whereas uncertainty quantifies the precision and potential error margin of a specific measurement.
a mistake in the experimental method used.
Experimental uncertainty is an inherent part of any measurement process due to equipment limitations, not a procedural mistake or blunder.
a mistake in the recording of a measurement.
A mistake in recording data is a human error, whereas uncertainty represents the natural limits of precision in the measuring instrument or process.
an estimate of the maximum likely difference between the measurement and the true value.
Experimental uncertainty provides a quantitative estimate of the range within which the true value of the measurement is expected to lie, accounting for inherent measurement limitations.
Many scientists have performed experiments to explore the interaction of light and matter.
Analyse how evidence from at least THREE such experiments has contributed to our understanding of physics.
Reveal Answer
Answers could include:
Reference to:
- Black body radiation experiments and the development of quantum physics
- Photoelectric experiments and the development of quantum physics
- Spectroscopy experiments and the development of astrophysics and the atomic model
- Polarisation experiments and the development of the wave nature of light
- Interference and diffraction and the development of the wave model of light
- Cosmic gamma rays and the development of theory of special relativity and/or the standard model.
| Descriptor | Marks |
|---|---|
| 8 |
| 7 |
The student response meets all criteria of the 5-mark band, and additionally meets the majority of criteria in the 7-mark band. | 6 |
| 5 |
The student response meets all criteria of the 3-mark band, and additionally meets the majority of criteria in the 5-mark band. | 4 |
Provides some information about evidence from an experiment AND/OR a link to physics | 3 |
The student response meets all criteria of the 1-mark band, and additionally meets the majority of criteria in the 3-mark band. | 2 |
Provides some relevant information | 1 |
None of the above | 0 |
Data can be described as precise when
it is the result of a careful investigation.
the experiment is repeated many times, and the results show little variation.
the same experimental methodology is used by different investigators.
it is close to the scientifically accepted value of the quantity being measured.
Reveal Answer
it is the result of a careful investigation.
While a careful investigation is important in science, it does not define precision, which specifically refers to the consistency of repeated measurements.
the experiment is repeated many times, and the results show little variation.
Precision refers to how close multiple measurements are to each other, meaning repeated trials will show very little variation.
the same experimental methodology is used by different investigators.
Having different investigators use the same methodology ensures standardization, but it does not guarantee that the resulting data will have low variance or high precision.
it is close to the scientifically accepted value of the quantity being measured.
Being close to the scientifically accepted or true value is the definition of accuracy, not precision.
Harriet and Tom were investigating how the speed, , of a falling object varied with the distance, , it had fallen.
They dropped a small steel ball, initially at rest, from the third floor of their school building. The speed of the ball was measured at six positions as it fell.
Air resistance can be ignored.
Which one of the following graphs of their data would be expected to result in a straight line through the origin?
versus
versus
versus
versus
Reveal Answer
versus
The kinematic equation for an object falling from rest is , meaning is proportional to . A graph of versus would result in a curve, not a straight line.
versus
Using the kinematic equation with an initial velocity of , we get . This shows that is directly proportional to , which produces a straight line through the origin.
versus
Based on the equation , is directly proportional to , not . Plotting versus would result in a quadratic curve.
versus
Since is proportional to , would be proportional to . Plotting versus would not produce a straight line.
Which one of the following best describes a hypothesis?
a testable scientific explanation
a well-tested scientific explanation
a scientific explanation by a famous scientist
a widely believed and highly plausible explanation
Reveal Answer
a testable scientific explanation
A hypothesis is fundamentally a proposed explanation for a phenomenon that can be tested through experimentation or observation. Testability is the core requirement of any scientific hypothesis.
a well-tested scientific explanation
A well-tested and broadly accepted scientific explanation is known as a scientific theory, not a hypothesis. A hypothesis is an initial proposal made before extensive testing occurs.
a scientific explanation by a famous scientist
The scientific method relies on empirical evidence and testability, not the authority or fame of the person making the claim.
a widely believed and highly plausible explanation
Popular belief or plausibility does not define a hypothesis. A hypothesis must be specifically testable through scientific methods, regardless of how many people currently believe it.