Physical Science: Matter, Forces & Energy — Sample exam worked answers
Student exam paperA rehearsal paper with separate worked solutions; use it before the final.
16 questions · 34 points · suggested 45 minutes
Student instructions
- Suggested time: 60 minutes; allow breaks or accommodations and record them.
- Work independently with a calculator, blank paper and the reference relationships printed in this paper. Grades 9, 11 and 12 may also use the course-linked NYSED reference tables. Use no lesson notes or answer key during an assessed attempt.
- Show reasoning and units for written tasks. All supplied datasets are illustrative; do not present them as measurements you collected.
- Objective items: 1 point each. Written items: 3 points each, one per criterion. A parent or teacher marks the written work; the app never grades an explanation automatically.
- Sample exam: try the whole paper before opening the worked key, then revisit the linked chapters. The sample and final are different papers; this is a course assessment, not an official Regents examination.
Reference relationships
| Relationship or tool | Conditions |
|---|---|
| Density | ρ=m/V; use equal units of volume. Water is approximately 1 g/mL in the introductory examples. |
| Motion | Average speed=distance/time; velocity=displacement/time; acceleration=change in velocity/time. |
| Force and work | Fnet=ma; W=Fd for an aligned constant force. Use the stated g value. |
| Energy and machines | KE=½mv²; ΔGPE=mgΔh; MA=output force/input force; efficiency=useful output/input×100%. |
| Particle and reaction models | Keep atom identity during a physical change; balance equations by coefficients, not subscripts. |
Coverage and marks
| Chapter | Questions | Points |
|---|---|---|
| Properties of Matter | 1, 2 | 4 |
| Phases of Matter | 3, 4 | 4 |
| Chemistry | 5, 6 | 4 |
| Forces | 7, 8 | 4 |
| Motion | 9, 10 | 4 |
| Work & Machines | 11, 12 | 4 |
| Energy & Heat Transfer | 13, 14 | 4 |
| Waves, Sound & Light | 15, 16 | 6 |
Parent / teacher marking guide
- Mark objective answers after submission. Written marks remain pending until a parent or teacher applies the three-point criteria.
- Accept scientifically equivalent wording and valid alternative methods. Award stated method credit for a correct model or substitution even if later arithmetic fails.
- A raw percentage describes this paper only; it is not a validated course grade or a certification. Review chapter-level evidence and the learner’s independent explanations.
- Record support and accommodations, save corrections and reassess with different tasks. Do not count copied solutions as independent mastery.
Question 1 · 1 point
Where are protons and neutrons located in an atom?
- In the nucleus
- Orbiting the nucleus
- Outside the atom entirely
- Only in charged atoms
Worked answer
In the nucleus
Protons and neutrons are packed together in the central nucleus.
1 point for the correct objective answer; no written-method marks for this item.
Question 2 · 3 points
Bag A survives 2 trips and uses 20 g of material; bag B survives 20 trips and uses 100 g. Compare material per trip, ignoring other impacts.
Worked answer
B uses 5 g/trip versus A's 10 g/trip in this model; the model alone does not settle total environmental impact.
Divide each bag's material by its number of trips: 20/2 and 100/20.
Compare 10 g/trip with 5 g/trip, while noting that energy, cleaning and disposal are not included.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: Divide each bag's material by its number of trips: 20/2 and 100/20.
- 1 point: reach a scientifically supported conclusion: B uses 5 g/trip versus A's 10 g/trip in this model; the model alone does not settle total environmental impact.
Question 3 · 1 point
While a pure liquid boils at fixed pressure, what happens to its temperature during the phase change?
- It stays the same until all the liquid has boiled away
- It rises steadily
- It drops suddenly
- It becomes negative
Worked answer
It stays the same until all the liquid has boiled away
At fixed pressure, added energy changes particle interactions during boiling rather than raising temperature while liquid and vapor coexist.
1 point for the correct objective answer; no written-method marks for this item.
Question 4 · 3 points
Two equal-mass water samples at 20°C and 60°C mix in an insulated container. Estimate the final temperature.
Worked answer
About 40°C, assuming no heat loss, evaporation or container energy change.
Equal masses of the same material exchange equal amounts of energy in this ideal model.
The final temperature lies halfway between: (20+60)/2=40°C.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: Equal masses of the same material exchange equal amounts of energy in this ideal model.
- 1 point: reach a scientifically supported conclusion: About 40°C, assuming no heat loss, evaporation or container energy change.
Question 5 · 1 point
Mixing two clear solutions produces a cloudy solid that settles to the bottom. This solid is called a…
- reactant
- catalyst
- precipitate
- solvent
Worked answer
precipitate
A solid that forms and settles out of a solution during a reaction is called a precipitate.
1 point for the correct objective answer; no written-method marks for this item.
Question 6 · 3 points
Compare the hydrogen-ion activity in solutions of pH 3 and pH 5.
Worked answer
The pH 3 solution has about 100 times the hydrogen-ion activity of pH 5 under comparable conditions.
The pH difference is 5−3=2.
Each step is a factor of 10, so the factor is 10×10=100.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: The pH difference is 5−3=2.
- 1 point: reach a scientifically supported conclusion: The pH 3 solution has about 100 times the hydrogen-ion activity of pH 5 under comparable conditions.
Question 7 · 1 point
If the net force on an object is zero, the object…
- must be at rest
- is either at rest or moving at constant velocity
- must be accelerating
- must be speeding up
Worked answer
is either at rest or moving at constant velocity
A zero net force means no change in motion — the object could be still, or cruising at a steady velocity.
1 point for the correct objective answer; no written-method marks for this item.
Question 8 · 3 points
A 200 N force is spread over 0.5 m². Find pressure and compare with the same force on 0.25 m².
Worked answer
400 Pa initially; reducing the area by half doubles pressure to 800 Pa.
Pressure=force/area=200/0.5=400 Pa.
Halving area gives 200/0.25=800 Pa.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: Pressure=force/area=200/0.5=400 Pa.
- 1 point: reach a scientifically supported conclusion: 400 Pa initially; reducing the area by half doubles pressure to 800 Pa.
Question 9 · 1 point
A train travels 300 km in 4 hours. What is its average speed?
Worked answer
75 km/h
Speed = distance ÷ time = 300 ÷ 4 = 75 km/h.
1 point for the correct objective answer; no written-method marks for this item.
Question 10 · 3 points
A net horizontal force of 12 N acts on a 4 kg cart. Calculate acceleration and identify the reaction to a hand's push.
Worked answer
3 m/s² in the net-force direction; the cart exerts an equal opposite force on the hand.
Acceleration=Fnet/m=12/4=3 m/s².
The reaction to the hand pushing the cart is the cart pushing the hand, on a different object.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: Acceleration=Fnet/m=12/4=3 m/s².
- 1 point: reach a scientifically supported conclusion: 3 m/s² in the net-force direction; the cart exerts an equal opposite force on the hand.
Question 11 · 1 point
You push a wall that remains still. Mechanical work on the wall is…
- zero
- equal to your mass
- always 100 J
- infinite
Worked answer
zero
The wall has no displacement.
1 point for the correct objective answer; no written-method marks for this item.
Question 12 · 3 points
A lift takes in 200 J and gives the load 150 J. Find efficiency and account for the remaining energy.
Worked answer
75% efficient; 50 J went to other parts of the system and surroundings.
Efficiency=(150/200)×100=75%.
Remaining energy=200−150=50 J in other transfers such as thermal energy and sound.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: Efficiency=(150/200)×100=75%.
- 1 point: reach a scientifically supported conclusion: 75% efficient; 50 J went to other parts of the system and surroundings.
Question 13 · 1 point
A 10 kg object sits on a shelf 2 m high. Find its gravitational potential energy. (g = 9.8 m/s²)
Worked answer
196 J
PE = mgh = 10 × 9.8 × 2 = 196 J.
1 point for the correct objective answer; no written-method marks for this item.
Question 14 · 3 points
Two bulbs are in series and one connection is removed. What happens? Compare with two independent parallel branches.
Worked answer
Both series bulbs go out; a bulb in the other intact parallel branch can stay lit.
Breaking the series path stops current through both bulbs.
Opening one parallel branch can leave the other branch's complete path intact.
Marking criteria
- 1 point: identify the appropriate model or mechanism for this task.
- 1 point: show the calculation or evidence in the worked steps: Breaking the series path stops current through both bulbs.
- 1 point: reach a scientifically supported conclusion: Both series bulbs go out; a bulb in the other intact parallel branch can stay lit.
Question 15 · 3 points
Two sources complete 8 and 12 cycles in 0.04 s with equal 2 mm amplitudes. Compare frequency, expected pitch and what remains unknown about received loudness.
Worked answer
The frequencies are 200 and 300 Hz. The second generally has higher pitch while amplitude is unchanged. Exact received loudness needs distance, medium and receiver conditions.
The frequencies are 200 and 300 Hz. The second generally has higher pitch while amplitude is unchanged. Exact received loudness needs distance, medium and receiver conditions.
Read the stated comparison conditions and identify a limitation.
Marking criteria
- 1 point: correct frequencies or decoded symbols.
- 1 point: correct mechanism or property comparison.
- 1 point: meaningful prediction limitation or threshold observation.
Question 16 · 3 points
An illustrative receiver uses threshold 0.5. Readings 0.7, 0.3, 0.52 and 0.2 form a message. Decode it and explain how ordinary sound and magnetic interaction differ across a vacuum gap.
Worked answer
The sequence is 1010; 0.52 is nearest the threshold. Ordinary sound needs matter, while magnetic interactions can cross a vacuum. A digital label does not guarantee freedom from noise errors.
The sequence is 1010; 0.52 is nearest the threshold. Ordinary sound needs matter, while magnetic interactions can cross a vacuum. A digital label does not guarantee freedom from noise errors.
Read the stated comparison conditions and identify a limitation.
Marking criteria
- 1 point: correct frequencies or decoded symbols.
- 1 point: correct mechanism or property comparison.
- 1 point: meaningful prediction limitation or threshold observation.