Units — NEET Physics MCQs with Solutions
Free NEET Physics Units MCQs with step-by-step solutions (36 questions). Part of Units and Dimensions. Practise online on Prepizo — no login needed.
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Questions with solutions
Q1 — Units · easy · theory
The SI unit of length is
A. foot
B. kilometre
C. metre ✓ Correct
D. centimetre
Solution: The SI base unit of length is the metre (m).
Q2 — Units · easy · theory
The SI unit of mass is
A. gram
B. pound
C. newton
D. kilogram ✓ Correct
Solution: The SI base unit of mass is the kilogram (kg).
Q3 — Units · easy · numerical
The number of fundamental (base) units in the SI system is
A. 7 ✓ Correct
B. 3
C. 5
D. 9
Solution: The SI has 7 base units: metre, kilogram, second, ampere, kelvin, mole, candela.
Q4 — Units · easy · theory
Which of the following is a fundamental (base) unit?
A. ampere ✓ Correct
B. watt
C. joule
D. newton
Solution: The ampere (electric current) is a base unit; the others are derived.
Q5 — Units · easy · theory
Which of the following is a derived unit?
A. kelvin
B. newton ✓ Correct
C. kilogram
D. second
Solution: Newton = kg·m/s² is built from base units, hence derived.
Q6 — Units · easy · theory
The SI unit of electric current is
A. volt
B. ohm
C. coulomb
D. ampere ✓ Correct
Solution: The ampere (A) is the SI base unit of current.
Q7 — Units · easy · theory
The SI unit of temperature is
A. fahrenheit
B. kelvin ✓ Correct
C. celsius
D. joule
Solution: The kelvin (K) is the SI base unit of thermodynamic temperature.
Q8 — Units · easy · theory
The SI unit of the amount of substance is
A. kilogram
B. gram
C. candela
D. mole ✓ Correct
Solution: The mole (mol) is the SI base unit for amount of substance.
Q9 — Units · easy · theory
The SI unit of luminous intensity is
A. lux
B. lumen
C. watt
D. candela ✓ Correct
Solution: The candela (cd) is the SI base unit of luminous intensity.
Q10 — Units · medium · theory
The SI unit of force, the newton, is equal to
A. kg·m⁻¹·s⁻²
B. kg·m²·s⁻²
C. kg·m·s⁻² ✓ Correct
D. kg·m·s⁻¹
Solution: Force = mass × acceleration, so 1 N = 1 kg·m/s².
Q11 — Units · easy · theory
The SI unit of work (or energy), the joule, equals
A. kg·m·s⁻²
B. kg·m²·s⁻¹
C. kg·m⁻¹·s⁻²
D. kg·m²·s⁻² ✓ Correct
Solution: 1 J = 1 N·m = kg·m²/s².
Q12 — Units · easy · theory
The SI unit of power is
A. watt ✓ Correct
B. pascal
C. newton
D. joule
Solution: Power is energy per unit time; the SI unit is the watt (1 W = 1 J/s).
Q13 — Units · easy · theory
The SI unit of pressure is
A. joule
B. newton
C. pascal ✓ Correct
D. bar
Solution: Pressure = force/area; the SI unit is the pascal (1 Pa = 1 N/m²).
Q14 — Units · easy · theory
One angstrom (Å) equals
A. 10⁻⁶ m
B. 10⁻⁹ m
C. 10⁻¹⁰ m ✓ Correct
D. 10⁻¹² m
Solution: 1 Å = 10⁻¹⁰ m, commonly used for atomic dimensions.
Q15 — Units · easy · theory
One light year is a unit of
A. time
B. speed
C. brightness
D. distance ✓ Correct
Solution: A light year is the distance light travels in one year (≈ 9.46×10¹⁵ m).
Q16 — Units · easy · theory
One micron (µm) equals
A. 10⁻³ m
B. 10⁻⁶ m ✓ Correct
C. 10⁻⁹ m
D. 10⁻¹² m
Solution: 1 micron = 1 micrometre = 10⁻⁶ m.
Q17 — Units · easy · theory
The unit "parsec" is used to measure
A. nuclear sizes
B. astronomical distances ✓ Correct
C. time
D. pressure
Solution: A parsec (≈ 3.26 light years) is used for astronomical distances.
Q18 — Units · easy · theory
One nanometre equals
A. 10⁻⁶ m
B. 10⁻¹² m
C. 10⁻⁹ m ✓ Correct
D. 10⁻³ m
Solution: The prefix nano means 10⁻⁹, so 1 nm = 10⁻⁹ m.
Q19 — Units · easy · numerical
The prefix "kilo" stands for
A. 10³ ✓ Correct
B. 10²
C. 10⁶
D. 10⁻³
Solution: Kilo = 10³ (e.g. 1 km = 1000 m).
Q20 — Units · easy · numerical
The prefix "mega" stands for
A. 10⁹
B. 10⁶ ✓ Correct
C. 10³
D. 10⁻⁶
Solution: Mega = 10⁶.
Q21 — Units · easy · numerical
The prefix "giga" stands for
A. 10⁹ ✓ Correct
B. 10³
C. 10⁶
D. 10¹²
Solution: Giga = 10⁹.
Q22 — Units · easy · numerical
One atmosphere of pressure is approximately
A. 760 Pa
B. 1×10⁷ Pa
C. 1×10³ Pa
D. 1.013×10⁵ Pa ✓ Correct
Solution: 1 atm ≈ 1.013×10⁵ Pa (≈ 760 mm of Hg).
Q23 — Units · medium · theory
The unit "electron volt" (eV) is a unit of
A. energy ✓ Correct
B. potential
C. current
D. charge
Solution: An eV is the energy gained by an electron across a 1 V potential difference (≈ 1.6×10⁻¹⁹ J).
Q24 — Units · easy · theory
Which of these is NOT an SI base quantity?
A. Length
B. Temperature
C. Time
D. Force ✓ Correct
Solution: Force is a derived quantity; length, time and temperature are base quantities.
Q25 — Units · medium · theory
The unit of frequency, the hertz, is equivalent to
A. s⁻¹ ✓ Correct
B. s
C. m/s
D. m·s⁻²
Solution: 1 Hz = 1 cycle per second = s⁻¹.
Q26 — Units · easy · theory
The CGS unit of force is the
A. poise
B. newton
C. dyne ✓ Correct
D. erg
Solution: In the CGS system, force is measured in dynes (1 N = 10⁵ dyne).
Q27 — Units · easy · theory
The CGS unit of energy is the
A. erg ✓ Correct
B. dyne
C. watt
D. joule
Solution: Energy in CGS is the erg (1 J = 10⁷ erg).
Q28 — Units · easy · numerical
A "quintal" equals
A. 1 kg
B. 10 kg
C. 100 kg ✓ Correct
D. 1000 kg
Solution: 1 quintal = 100 kg (and 1 tonne = 10 quintals = 1000 kg).
Q29 — Units · easy · theory
The unit "amu" (atomic mass unit) is used to measure
A. mass ✓ Correct
B. energy
C. charge
D. length
Solution: 1 amu ≈ 1.66×10⁻²⁷ kg — the mass scale for atoms.
Q30 — Units · easy · theory
The horsepower (hp) is a unit of
A. torque
B. energy
C. force
D. power ✓ Correct
Solution: Horsepower measures power; 1 hp ≈ 746 W.