Free Physics Mock Test – Chapter-wise Test Series (Test 1)
NEET Physics Free Mock Test
TUnit and Measurement — Chapter 1
If you are preparing for NEET 2026, you cannot afford to skip Units & Measurements. This chapter from Class 11 Physics is one of the most scoring topics in the exam. Every year, NEET asks 1–2 direct questions from this chapter — and with negative marking in play, knowing this topic with 100% confidence can make a real difference to your final score.
Whether you are a first-time aspirant or repeater, this guide will help you build a rock-solid foundation in Units & Measurements, understand the most-tested concepts, and avoid common mistakes that cost students marks.
What is the SI system? The 7 Base Units You Must Know
The International System of Units (SI) is the globally accepted standard for scientific measurement. It has exactly 7 base units — a fact directly tested in NEET exams.
| Physical Quantity | SI Base Unit | Symbol |
|---|---|---|
| Length | Metre | m |
| Mass | Kilogram | kg |
| Time | Second | s |
| Electric Current | Ampere | A |
| Temperature | Kelvin | K |
| Amount of Substance | Mole | mol |
| Luminous Intensity | Candela | cd |
Key NEET Tip: Newton, Pascal, Joule, and Watt are all derived units — not base units. This distinction is a very common trap in MCQs.
Dimensional Analysis: The Most Powerful Tool in Physics
Dimensional analysis is used to derive formulas, check equation correctness, and convert between unit systems. Every NEET aspirant must be able to write the dimensional formula of common physical quantities instantly.
Most Important Dimensional Formulas:
- Force: [MLT⁻²]
- Work / Energy: [ML²T⁻²]
- Power: [ML²T⁻³]
- Pressure: [ML⁻¹T⁻²]
- Planck’s Constant: [ML²T⁻¹] — unit is Joule-second (J·s)
Pro Tip: Torque and Energy share the same dimensional formula [ML²T⁻²], but they are physically different quantities. NEET frequently tests this concept.
Significant Figures: Rules That Students Always Forget
Significant figures represent the precision of a measurement. Here are the three rules most commonly tested in NEET:
- Non-zero digits are always significant (e.g., 452 has 3 significant figures).
- Leading zeros are never significant (e.g., 0.0045 has only 2 significant figures).
- Trailing zeros after a decimal point are significant (e.g., 0.00450 has 3 significant figures — 4, 5, and 0).
This last rule — trailing zeros after a decimal — is the most frequently missed in NEET MCQs.
Error Analysis: How to Calculate Maximum Percentage Error
For a quantity like kinetic energy KE = ½mv², the percentage error formula is:
% Error in KE = % Error in m + 2 × % Error in v
The factor of 2 comes from the power of velocity in the formula. If the percentage error in mass is 2% and in velocity is 3%, then the maximum possible error in kinetic energy = 2% + 2(3%) = 8%.
This type of numerical is extremely common in NEET and can be solved in under 30 seconds once you know the rule.
How to Use Mock Tests to Master This Chapter
Practicing with topic-wise mock tests is the fastest way to master Units & Measurements. A good mock test will:
- Test your recall of dimensional formulas under time pressure
- Expose gaps in your understanding of SI base units vs. derived units
- Train you to apply the error analysis formula correctly in numericals
After every mock test, review each explanation carefully — especially for questions you got wrong. Understanding why an answer is correct builds long-term retention far better than simply memorizing answers.
Quick Revision Checklist Before Your NEET Exam
- Know all 7 SI base units by heart
- Memorize dimensional formulas for at least 15 key quantities
- Practice significant figures rules with examples
- Solve at least 5 error analysis numericals
- Attempt at least one full mock test on this chapter
Conclusion
Units & Measurements may seem like a small chapter, but it carries guaranteed marks in NEET if prepared correctly. Focus on SI base units, dimensional formulas, significant figures, and error analysis — these four areas cover almost every question this chapter has to offer. Pair your reading with regular mock test practice, and you will walk into the exam with full confidence on this topic.