Skip to content
Try on iPad

S.I. units: OCR A‑Level Physics A questions

Every OCR A-Level Physics A exam question on 2.1.2 S.I. units, 2016–2025, with its mark scheme and examiner’s report.

Find questions1,877
Calculations

1,877 questions

  1. Q1

    June 2025 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2025 Paper 1, question 1: Which of these physical constants requires the greatest number of different base SI units? A Avogadro constant, NA B Boltzmann constant, k C Gravitational const

  2. Q9

    June 2025 · AS Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2025 AS Paper 1, question 9: The Young modulus of a material is 2.1 × 109 Pa. 9 What is 2.1 × 109 Pa numerically equal to? A 2.1 GPa B 2.1 kPa C 2.1 MPa D 2.1 TPa Your answer [1]

  3. Q1

    June 2024 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2024 Paper 1, question 1: Which row in the table shows two equivalent physical quantities? A 0 °C –273.15 K 1 kg m s–1 B 1000 N s C 10 kW 10 000 N m 0.0010 N m–2 D 1.0 mPa Your answer [1

  4. Q2

    June 2024 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2024 Paper 1, question 2: What are the SI base units of the Boltzmann constant k? J K–1 A kg m s–2 K–1 B kg m2 s–2 K–1 C N m K–1 D Your answer [1]

  5. Q1

    June 2024 · Paper 2

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2024 Paper 2, question 1: What are the base units of a kilowatt‑hour? A J kg m2 s–1 B kg m2 s–2 C D W s Your answer [1]

  6. Q1

    June 2024 · AS Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2024 AS Paper 1, question 1: Which is an S.I. base unit? A amp B coulomb C ohm D volt Your answer [1]

  7. Q21(a)(i)

    June 2023 · Paper 1

    2 marks2.1.2 S.I. units
    The whole paper ↗
    June 2023 Paper 1, question 21(a)(i): Show that the equation above is homogeneous by reducing the equation to SI base units. [2]

  8. Q1

    June 2023 · Paper 2

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2023 Paper 2, question 1: Which of these units is a base unit? A A B J m2 C D N Your answer [1]

  9. Q11

    June 2022 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2022 Paper 1, question 11: Which pair of quantities do not have the same, or equivalent, units? A acceleration, gravitational field strength B angular frequency, angular velocity C gravit

  10. Q20(a)

    June 2022 · Paper 1

    2 marks2.1.2 S.I. units
    The whole paper ↗
    June 2022 Paper 1, question 20(a): For a simple harmonic oscillator, the acceleration a is given by the equation a = –ω 2x, where ω is the angular frequency and x is the displacement. Show that t

  11. Q17(a)

    June 2022 · Paper 2

    2 marks2.1.2 S.I. units
    The whole paper ↗
    June 2022 Paper 2, question 17(a): In the equation above, hc λ is the energy of a photon emitted from the LED. Determine the S.I. base units for h. base units = [2]

  12. Q2

    November 2021 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    November 2021 Paper 1, question 2: Which one of the following prefixes represents the smallest multiplication factor? A femto (f) B micro (μ) C nano (n) D pico (p) Your answer [1]

  13. Q16(a)(i)

    November 2021 · Paper 1

    2 marks2.1.2 S.I. units
    The whole paper ↗
    November 2021 Paper 1, question 16(a)(i): Show that the equation s = 1 2 gt 2 is homogeneous, with both sides of the equation having the same base units. [2]

  14. Q8

    November 2021 · AS Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    November 2021 AS Paper 1, question 8: Which pair of quantities have the same S.I. base units? A strain, elastic potential energy B strain, force constant C stress, force constant D stress, Young mod

  15. Q17

    November 2021 · AS Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    November 2021 AS Paper 1, question 17: A student is recording results in a table. The calculated value for the stress in a wire is 7 260 000 Pa. Which of the following is correct for the heading in t

  16. Q2

    November 2020 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    November 2020 Paper 1, question 2: Which pair of quantities have the same S.I. base units? A force, strain B force, stress C pressure, stress D strain, upthrust Your answer [1]

  17. Q19(a)

    November 2020 · Paper 2

    2 marks2.1.2 S.I. units
    The whole paper ↗
    November 2020 Paper 2, question 19(a): The Planck constant h is an important fundamental constant in quantum physics. Determine the S.I. base units for h. base units = [2]

  18. Q17

    November 2020 · AS Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    November 2020 AS Paper 1, question 17: Which pair of quantities have the same S.I. base units? A force, energy B moment, momentum C power, work done D work done, moment Your answer [1]

  19. Q22(a)

    November 2020 · AS Paper 1

    2 marks2.1.2 S.I. units
    The whole paper ↗
    November 2020 AS Paper 1, question 22(a): The S.I. base units for F are kg m s−2. Show that the S.I. base units for k are kg m−1. [2]

  20. Q1

    June 2019 · Paper 1

    1 mark2.1.2 S.I. units
    The whole paper ↗
    June 2019 Paper 1, question 1: Which set of prefixes A, B, C or D are in order of increasing magnitude? A micro, milli, centi, kilo B milli, centi, micro, kilo C kilo, centi, milli, micro D c
All 35 questions on S.I. units, as a list
  1. June 2025, Paper 1, Q1 (1 mark): Which of these physical constants requires the greatest number of different base SI units? A Avogadro constant, NA B Boltzmann constant, k C Gravitational const
  2. June 2025, AS Paper 1, Q9 (1 mark): The Young modulus of a material is 2.1 × 109 Pa. 9 What is 2.1 × 109 Pa numerically equal to? A 2.1 GPa B 2.1 kPa C 2.1 MPa D 2.1 TPa Your answer [1]
  3. June 2024, Paper 1, Q1 (1 mark): Which row in the table shows two equivalent physical quantities? A 0 °C –273.15 K 1 kg m s–1 B 1000 N s C 10 kW 10 000 N m 0.0010 N m–2 D 1.0 mPa Your answer [1
  4. June 2024, Paper 1, Q2 (1 mark): What are the SI base units of the Boltzmann constant k? J K–1 A kg m s–2 K–1 B kg m2 s–2 K–1 C N m K–1 D Your answer [1]
  5. June 2024, Paper 2, Q1 (1 mark): What are the base units of a kilowatt‑hour? A J kg m2 s–1 B kg m2 s–2 C D W s Your answer [1]
  6. June 2024, AS Paper 1, Q1 (1 mark): Which is an S.I. base unit? A amp B coulomb C ohm D volt Your answer [1]
  7. June 2023, Paper 1, Q21(a)(i) (2 marks): Show that the equation above is homogeneous by reducing the equation to SI base units. [2]
  8. June 2023, Paper 2, Q1 (1 mark): Which of these units is a base unit? A A B J m2 C D N Your answer [1]
  9. June 2022, Paper 1, Q11 (1 mark): Which pair of quantities do not have the same, or equivalent, units? A acceleration, gravitational field strength B angular frequency, angular velocity C gravit
  10. June 2022, Paper 1, Q20(a) (2 marks): For a simple harmonic oscillator, the acceleration a is given by the equation a = –ω 2x, where ω is the angular frequency and x is the displacement. Show that t
  11. June 2022, Paper 2, Q17(a) (2 marks): In the equation above, hc λ is the energy of a photon emitted from the LED. Determine the S.I. base units for h. base units = [2]
  12. November 2021, Paper 1, Q2 (1 mark): Which one of the following prefixes represents the smallest multiplication factor? A femto (f) B micro (μ) C nano (n) D pico (p) Your answer [1]
  13. November 2021, Paper 1, Q16(a)(i) (2 marks): Show that the equation s = 1 2 gt 2 is homogeneous, with both sides of the equation having the same base units. [2]
  14. November 2021, AS Paper 1, Q8 (1 mark): Which pair of quantities have the same S.I. base units? A strain, elastic potential energy B strain, force constant C stress, force constant D stress, Young mod
  15. November 2021, AS Paper 1, Q17 (1 mark): A student is recording results in a table. The calculated value for the stress in a wire is 7 260 000 Pa. Which of the following is correct for the heading in t
  16. November 2020, Paper 1, Q2 (1 mark): Which pair of quantities have the same S.I. base units? A force, strain B force, stress C pressure, stress D strain, upthrust Your answer [1]
  17. November 2020, Paper 2, Q19(a) (2 marks): The Planck constant h is an important fundamental constant in quantum physics. Determine the S.I. base units for h. base units = [2]
  18. November 2020, AS Paper 1, Q17 (1 mark): Which pair of quantities have the same S.I. base units? A force, energy B moment, momentum C power, work done D work done, moment Your answer [1]
  19. November 2020, AS Paper 1, Q22(a) (2 marks): The S.I. base units for F are kg m s−2. Show that the S.I. base units for k are kg m−1. [2]
  20. June 2019, Paper 1, Q1 (1 mark): Which set of prefixes A, B, C or D are in order of increasing magnitude? A micro, milli, centi, kilo B milli, centi, micro, kilo C kilo, centi, milli, micro D c
  21. June 2019, Paper 1, Q10 (1 mark): Which of the following shows the correct base units for pressure? kg m–2 A kg m–2 s–2 B kg m–1 s–2 C kg m2 s–3 D [1] Your answer
  22. June 2019, Paper 2, Q18(b) (2 marks): The S.I. base units for the ohm (Ω) are kg m2 s–3 A–2. Use the equation R = ρL A to determine the S.I. base units for resistivity ρ. base units for ρ [2] Questi
  23. June 2019, AS Paper 1, Q1 (1 mark): The table below shows four physical quantities and their units. Which row is correct? Physical quantity Unit A strain pascal B charge coulomb C power joule D fo
  24. June 2019, AS Paper 1, Q17 (1 mark): Power has base units kg m2 s–3. What are the base units for intensity? kg s–3 A kg m s–3 B kg m2 s–3 C kg m4 s–3 D Your answer [1]
  25. June 2018, Paper 1, Q1 (1 mark): Which of the following units is not an S.I. base unit? A ampere B mole C volt D kilogram Your answer [1]
  26. June 2018, Paper 1, Q18(b)(i) (3 marks): Show that the equation is homogeneous with both sides of the equation having the same base units. [3]
  27. June 2018, Paper 2, Q16(a) (2 marks): Derive the S.I. base units for resistance. base units: [2]
  28. June 2018, AS Paper 1, Q20 (1 mark): What are the correct base units for work done or energy? A kg m kg m s−2 B kg m2 s−1 C kg m2 s−2 D Your answer [1]
  29. June 2017, Paper 1, Q17(b)(ii) (2 marks): The students made a reading of p of 37.0 ± 0.5 psi when θ was 44 ± 1 °C. Convert this value of p from psi to kPa. Complete the table for the missing value of p.
  30. June 2017, Paper 2, Q3 (1 mark): Which is not a unit of energy? A kW h B eV C J D W Your answer [1]
  31. June 2017, Paper 2, Q17(a) (1 mark): State one S.I. base quantity other than length, mass and time. [1]
  32. June 2017, AS Paper 1, Q20 (1 mark): Which is not an International System (S.I.) base unit? A second (s) B kelvin (K) C kilogram (kg) D coulomb (C) Your answer [1]
  33. June 2017, AS Paper 1, Q26(a) (1 mark): The SI base units of v, T and μ are shown below. m s–1 T kg m s–2 μ kg m–1 v Show that the equation above is homogeneous. [1]
  34. June 2017, AS Paper 2, Q1(b)(i) (1 mark): Show that the train is travelling at about 17 ms−1. [1]
  35. June 2016, AS Paper 2, Q4(a) (3 marks): The unit of potential difference is the volt. Use the equation W = VQ to show that the volt may be written in base units as kg m2 A−1 s−3. [3]

Questions, mark schemes and examiner’s reports are © OCR, from their published past papers. Plumi isn’t affiliated with any exam board. Want whole papers? Every OCR A-Level Physics A paper, or our free OCR-style practice pack.

Rather write your answers by hand on iPad? Plumi marks them against the same mark schemes.