New Curriculum Third Term Physics examination for SS 1

Class: SSS 1
Term: Third Term
Subject: Physics
Time: 1 hour 30 minutes
Total Marks: 70

SECTION A: OBJECTIVES (40 MARKS)
Instruction: Answer ALL questions. Each question carries 1 mark.

1. A light sensor changes its electrical response as illumination changes. Its role in a control circuit is to (a) store all energy required by the circuit   (b) replace the power source permanently   (c) measure liquid pressure without a transducer   (d) convert a physical condition into a detectable electrical signal
2. A Vernier calliper's jaws are likely to become damaged if it is stored ________. (a) in its labelled storage box   (b) clean and closed in a protective case   (c) after careful wiping   (d) with the jaws under unnecessary force or impact
3. An instrument's precision cannot be improved by ________ alone. (a) rewriting a scale reading with more decimal places   (b) using a calibrated, finer-scale instrument   (c) reducing parallax during reading   (d) taking repeated measurements
4. A roadside monitor records higher air-pollutant concentrations during heavy traffic. A scientifically sound conclusion is that (a) all pollutants in the city arise exclusively from cars   (b) pollution disappears as soon as traffic stops   (c) the measurements show an association requiring further controlled investigation   (d) the instrument reading proves which individual driver caused the pollution
5. The study of a simple cell illustrates collaboration between physics and chemistry because it combines (a) electrochemical reactions with electrical measurements   (b) electric potential without an electrolyte or reactions   (c) chemical changes measured without any electrical circuit   (d) two unconnected electrodes assumed to produce current indefinitely
6. An instrument record shows that a balance has not been calibrated for months. The next appropriate step is to (a) assume all instruments share the same accuracy   (b) erase past measurements without inspection   (c) verify calibration status before relying on precise readings   (d) record only the balance colour
7. Which design is most convincing when testing a prototype light sensor? (a) Record one unexplained reading as the final result   (b) Keep supply conditions constant and vary only the light reaching the detector   (c) Cover both the sensor and measurement display   (d) Change the light and the battery voltage together
8. Which measurement would best help compare two simple cells fairly? (a) Number of letters in the metal names   (b) Length of the laboratory table   (c) Colour of each beaker's label   (d) Terminal voltage measured under comparable circuit conditions
9. In a school demonstration of biogas, organic waste is placed in an airtight digester. The condition is important because microbial decomposition occurs mainly ________. (a) without oxygen   (b) only in a vacuum   (c) under intense ultraviolet light   (d) through a high-voltage discharge
10. The best method for testing a small biogas model for leaks is to (a) seal the gas outlet permanently and keep heating   (b) taste the liquid leaving the digester   (c) check fittings safely with soapy water and monitor pressure without ignition   (d) hold an open flame against each joint
11. A solar collector's dark absorber is selected mainly because a dark surface ________. (a) has zero heat capacity   (b) absorbs a larger fraction of incident radiation   (c) creates electric current without a cell   (d) prevents thermal radiation completely
12. Which precaution is necessary when collecting small amounts of biogas for an educational demonstration? (a) Vent all gas into a closed classroom   (b) Work with supervision and keep ignition sources away from leaking gas   (c) Leave pressure uncontrolled   (d) Use only glass containers without checking pressure ratings
13. A student reports a chipped glass lens on a measuring instrument. What should happen next? (a) Hide the damage to avoid a record   (b) Continue using it while pressing harder   (c) Apply an unspecified solvent during operation   (d) Remove it from use and refer it for safe repair or replacement
14. The main reason a researcher separates training data from test data is ________. (a) to ensure the instrument never needs calibration   (b) to assess performance on examples not used to fit the model   (c) to remove the need for measurement units   (d) to make every graph a straight line
15. ________ should be checked before a measurement instrument is issued for practical work. (a) The warranty expiry date but not current accuracy   (b) The previous purchase invoice instead of functionality   (c) Its working condition and calibration status   (d) The manufacturer colour code without a function test
16. The correct care procedure for a measuring cylinder after a harmless aqueous experiment is to (a) clean, rinse and return it securely to its designated place   (b) strike it against the bench to empty it   (c) leave residues until the next class   (d) heat it over an open flame regardless of glass type
17. An AI model estimates experimental readings from examples. This is best described as (a) a device that measures mass mechanically   (b) learning relationships from training data and applying them to new inputs   (c) replacing experimental observations with arbitrary labels   (d) proving every physical law without testing
18. ________ can be estimated by recording a sound level meter's readings at several distances from a source. (a) The sound source frequency without spectral analysis   (b) The variation in sound level with distance   (c) The total electrical energy used by the sound source   (d) A precise source power rating using only one level reading
19. A lab technician keeps chemicals and electrical test equipment in separate labelled storage. The main benefit is (a) safer retrieval and reduced accidental damage or misuse   (b) making measurement errors impossible   (c) preventing all future equipment replacement costs   (d) increasing every instrument's operating voltage
20. A simple solar heater loses heat rapidly on windy days. Which modification is most appropriate? (a) Add a transparent cover and insulation to reduce heat losses   (b) Paint the absorber with a highly reflective silver finish only   (c) Place the water container permanently in the shade   (d) Remove insulation from all sides
21. Which action should NOT be taken when a person may be in contact with a live conductor? (a) Keep bystanders away from the hazard   (b) Isolate the power source by a safe method   (c) Call for qualified emergency help   (d) Touch the person directly before isolating the supply
22. A digester produces gas while organic slurry decomposes. The energy pathway is best explained as (a) heat flow alone converts a sealed vessel into a gas generator   (b) mechanical mixing directly creates methane without decomposition   (c) electric current in a metal lid supplies the whole gas volume   (d) chemical energy stored in biomass becomes combustible gas
23. A simple cell can produce a current because ________ reactions at its electrodes release energy that supports charge movement. (a) nuclear   (b) gravitational   (c) chemical   (d) elastic
24. In a simple cell experiment, removing the connecting wire causes the current to stop mainly because ________. (a) the electrodes cease to be matter   (b) the conducting circuit is open   (c) the metals instantly lose their atoms   (d) all solutions become perfect insulators
25. An experiment gives times 1, 2, 3, 4 s and distances 2, 4, 6, 8 m. A graph of distance against time indicates (a) speed increasing by 2 m/s each second   (b) uniform acceleration of 2 m/s²   (c) uniform speed of 2 m/s   (d) deceleration to zero
26. A 2 m metal rail expands by 1.2 mm on warming. Its new length is ________. (a) 2.0012 m   (b) 2.12 m   (c) 2.012 m   (d) 2.00012 m
27. A pupil enters measurements into a spreadsheet. The correct step before drawing an XY plot is to (a) sort values alphabetically as words   (b) place independent and dependent numerical values in labelled columns   (c) replace all units with unspecified letters   (d) make the horizontal axis the student's name
28. Which information is most useful in an equipment-use register? (a) An equipment catalogue giving model and list prices only   (b) A stock count without user or issue dates   (c) Instrument ID, borrower, date and condition   (d) A calibration sticker with no borrowing history
29. A chart showing temperature against time is most informative when its axes have ________. (a) a single ordinate value repeated at each time   (b) unlabelled axes with a plotted line only   (c) a numerical axis with time values shown as categorical words   (d) appropriate scales and units
30. A student notices a damaged mains cable on a laboratory instrument. The correct immediate action is to (a) twist the exposed wires together during use   (b) continue working if no sparks appear   (c) stop using it, isolate power safely and report the fault   (d) touch the bare conductor to determine whether it is live
31. ________ detects the change in illumination in an automatic streetlight circuit. (a) motion timer   (b) pressure gauge   (c) temperature sensor   (d) light sensor
32. The main reason physical measurements matter in environmental science is ________. (a) they make pollution harmless automatically   (b) they quantify changes such as sound, heat and radiation for evidence-based decisions   (c) they replace every chemical and biological observation   (d) they provide identical values at all locations
33. Which change makes a physics-based environmental investigation more reliable? (a) Repeat measurements at stated locations and comparable times   (b) Change the instrument and location for every reading without records   (c) Discard results that disagree with predictions   (d) Take one measurement with no units
34. When a calculated mean differs greatly from most repeated measurements, the student should first (a) change every value until the graph appears straight   (b) report the largest reading as the only accurate result   (c) delete all readings except the mean   (d) inspect the original data for transcription errors or anomalous values
35. The main purpose of suitable protective equipment is to (a) make every hazardous procedure safe regardless of conditions   (b) eliminate the need for emergency response plans   (c) reduce exposure to identified laboratory hazards   (d) replace careful working procedures
36. A machine-learning tool fits a smooth curve to noisy laboratory readings. A responsible conclusion is that the curve (a) eliminates the need to retain original measurements   (b) must be the exact physical law in every case   (c) guarantees that any outlier is false   (d) is a model requiring comparison with observed data
37. All the following are examples of measured inputs to sensors EXCEPT (a) movement near a doorway   (b) ambient temperature   (c) the numerical result of an algebra exercise   (d) surface pressure
38. A solar thermal collector differs from a photovoltaic panel because its intended useful output is primarily (a) heat rather than electrical energy   (b) electrical current rather than heat   (c) fuel from decomposed organic waste   (d) a magnetic field rather than light absorption
39. Which of the following statements about AI-assisted data analysis is NOT justified? (a) Biases in training data may influence results   (b) Its predictions are always accurate because a computer generated them   (c) A human should check predictions against evidence   (d) Results depend on the quality of input data
40. A warning triangle showing a lightning symbol indicates a risk of ________. (a) slippery floor only   (b) biological contamination only   (c) optical magnification   (d) electrical hazard

SECTION B: THEORY (30 MARKS)
Instruction: Answer Question 1 and any other TWO questions. Each question carries 10 marks.

Question 1
(a) Compare a photovoltaic panel and a solar thermal collector in terms of inputs and useful outputs. (4 marks)
(b) A 2.0 m strip expands by 1.6 mm when heated. Express the new length in metres and suggest two design precautions. (6 marks)

Question 2
(a) A pupil records distances 3, 6, 9, 12 m at times 1, 2, 3, 4 s. Determine gradient and describe the motion. (5 marks)
(b) Identify two ways spreadsheet analysis can distort conclusions if data are handled poorly. (5 marks)

Question 3
(a) Describe a safe procedure for testing a light sensor using a lamp and measuring device. (6 marks)
(b) Explain two limitations of using AI to interpret the readings. (4 marks)

Question 4
(a) Outline a safe school-scale biogas production demonstration and two measurable observations. (6 marks)
(b) Describe how a simple cell combines chemical and physical processes. (4 marks)

Objective Marking Scheme
Question 1 – ✅ (d) convert a physical condition into a detectable electrical signal
Question 2 – ✅ (d) with the jaws under unnecessary force or impact
Question 3 – ✅ (a) rewriting a scale reading with more decimal places
Question 4 – ✅ (c) the measurements show an association requiring further controlled investigation
Question 5 – ✅ (a) electrochemical reactions with electrical measurements
Question 6 – ✅ (c) verify calibration status before relying on precise readings
Question 7 – ✅ (b) Keep supply conditions constant and vary only the light reaching the detector
Question 8 – ✅ (d) Terminal voltage measured under comparable circuit conditions
Question 9 – ✅ (a) without oxygen
Question 10 – ✅ (c) check fittings safely with soapy water and monitor pressure without ignition
Question 11 – ✅ (b) absorbs a larger fraction of incident radiation
Question 12 – ✅ (b) Work with supervision and keep ignition sources away from leaking gas
Question 13 – ✅ (d) Remove it from use and refer it for safe repair or replacement
Question 14 – ✅ (b) to assess performance on examples not used to fit the model
Question 15 – ✅ (c) Its working condition and calibration status
Question 16 – ✅ (a) clean, rinse and return it securely to its designated place
Question 17 – ✅ (b) learning relationships from training data and applying them to new inputs
Question 18 – ✅ (b) The variation in sound level with distance
Question 19 – ✅ (a) safer retrieval and reduced accidental damage or misuse
Question 20 – ✅ (a) Add a transparent cover and insulation to reduce heat losses
Question 21 – ✅ (d) Touch the person directly before isolating the supply
Question 22 – ✅ (d) chemical energy stored in biomass becomes combustible gas
Question 23 – ✅ (c) chemical
Question 24 – ✅ (b) the conducting circuit is open
Question 25 – ✅ (c) uniform speed of 2 m/s
Question 26 – ✅ (a) 2.0012 m
Question 27 – ✅ (b) place independent and dependent numerical values in labelled columns
Question 28 – ✅ (c) Instrument ID, borrower, date and condition
Question 29 – ✅ (d) appropriate scales and units
Question 30 – ✅ (c) stop using it, isolate power safely and report the fault
Question 31 – ✅ (d) light sensor
Question 32 – ✅ (b) they quantify changes such as sound, heat and radiation for evidence-based decisions
Question 33 – ✅ (a) Repeat measurements at stated locations and comparable times
Question 34 – ✅ (d) inspect the original data for transcription errors or anomalous values
Question 35 – ✅ (c) reduce exposure to identified laboratory hazards
Question 36 – ✅ (d) is a model requiring comparison with observed data
Question 37 – ✅ (c) the numerical result of an algebra exercise
Question 38 – ✅ (a) heat rather than electrical energy
Question 39 – ✅ (b) Its predictions are always accurate because a computer generated them
Question 40 – ✅ (d) electrical hazard

Theory Marking Scheme
Question 1
(a) Both receive sunlight (1); PV outputs electrical energy (2); thermal collector delivers heat (1). [4 marks]
(b) 1.6 mm=0.0016 m; final 2.0016 m (2); expansion gap (2); avoid rigid constrained joints or provide sliding mounts (2). [6 marks]
Question 2
(a) Gradient=(12−3)/(4−1)=3 m/s (3), constant speed (2). [5 marks]
(b) Award 2 each for incorrect units/axes, sorting mismatched columns, excluding inconvenient readings, mistyped formulas; 1 for explaining why check raw data. [5 marks]
Question 3
(a) Stable power and known suitable wiring (2); vary illumination at consistent geometry (2); record readings, repeat/compare (2). [6 marks]
(b) Data errors or training bias affect outputs (2); predicted trends must be checked against observations, not treated as proof (2). [4 marks]
Question 4
(a) Supervised sealed suitable organic digester (2); no flame/leak hazards and managed pressure/ventilation (2); track temperature/time/gas volume or pressure (2). [6 marks]
(b) Electrode chemical reactions make a potential difference (2); closed electric circuit permits charge flow measurable as current/voltage (2). [4 marks]