Physics · Science General

Units and Measurement

998 Questions

Master the fundamentals of physics with these practice questions on units and measurement. The topics include fundamental SI units, derived quantities, and specific units for power, force, and light. These questions are essential for building a strong foundation for competitive exams.

SI fundamental unitsUnits of powerDerived quantities unitsThermal energy unitsVolume measurement unitsElectric current units

Units and Measurement Questions

Multiple choice introduction to induction electromagnetic induction electromagnetic induction and alternating currents physics

The unit of inductance is equivalent to

  1. $\dfrac {volt\times ampere}{second}$
  2. $\dfrac { ampere}{volt\times second}$
  3. $\dfrac {volt}{Ampere\times second}$
  4. $\dfrac {volt\times second}{ampere}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$As \, \varepsilon \, = \,  L \, \dfrac{dI}{dt},$
$L \, = \, \varepsilon \dfrac{dt}{dI} \Rightarrow \, L \, = \, \dfrac{volt \times second}{ampere}$

Multiple choice introduction to induction electromagnetic induction electromagnetic induction and alternating currents physics

Henry, the SI unit of inductance can be written as :

  1. weber ampere$^{-1}$
  2. volt second ampere$^{-1}$
  3. joule ampere$^{-1}$
  4. ohm s$^{-1}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The SI unit of inductance is Henry,
$\displaystyle L =-\dfrac{e}{\dfrac{di}{dt}}$
SI unit $= \displaystyle \dfrac{volt}{A} \times s$
$=volt \times second \times  ampere^{-1}$

Multiple choice introduction to induction electromagnetic induction electromagnetic induction and alternating currents physics

Multiple Correct Answers Type
The SI unit of inductance, henry, can be written as

  1. Weber/ampere

  2. Volt-second / ampere
  3. $Joule / (ampere)^2$

  4. Ohm-second
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

$L=\cfrac{\phi}{i}$

$L=\cfrac{weber}{Ampere}$
$V=L\cfrac{Ldi}{dt}$
$L\to$ volt.second/ampere
$E=\cfrac{1}{2}Li^2$
$L\to $joule/(ampere$)^2$
$\omega L=X _L$
$L\to$ohm.second
Hence all are correct.

Multiple choice introduction to induction electromagnetic induction electromagnetic induction and alternating currents physics

The SI unit of inductance, the henry, can be written as :

  1. weber / ampere

  2. volt second / ampere
  3. joule / ampere$^2$

  4. ohm second
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

$ L\dfrac{dI}{dt} = emf = \dfrac{d\phi}{dt}$


a) $ [L] = weber / ampere $

b) $ [L] = volt.second / ampere $

c) $ Joule = volt \times ampere \times second $

$ \Rightarrow volt \times second = Joule / ampere$

$ \Rightarrow [L] = joule/ ampere^2$

d) $ V = IR \Rightarrow volt = ampere.ohm$

$\Rightarrow [L] = ohm.second$.

Multiple choice introduction to induction electromagnetic induction electromagnetic induction and alternating currents physics

Which of the following units denotes the dimensions ${M}{L}^{2}/{Q}^{2}$, where ${Q}$ denotes the electric charge?

  1. $Weber$ ($Wb$)
  2. $Wb$$/\mathrm{m}^{2}$
  3. $Henry$ ($H$)
  4. $\mathrm{H}/\mathrm{m}^{2}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Weber $=ML^2T^{-2}I^{-1}$
$=ML^2T^{-2}Q^{-1}T=ML^2T^{-1}Q^{-1}$   ($I=QT^{-1}$)
Henry H is  SI unit of inductance. 
$H=ML^2T^{-2}I^{-2}$     also $I=QT^{-1}$
so $H=ML^2T^{-2}Q^{-2}T^2=ML^2Q^{-2}$

Multiple choice evs weather, climate and adaptation of animals to different climates climate and weather weather, climate and adaptations of animals to climate atmosphere and its components

The unit of pressure most commonly found on a surface weather map is:

  1. Inches of mercury (Hg)

  2. Millibars or hectopascals

  3. Pounds per square inch

  4. Millimeters of mercury (Hg)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Meteorologists use millibars (mb) or hectopascals (hPa) as the standard units for atmospheric pressure on surface weather maps. These units are preferred for their consistency in scientific calculations.

Multiple choice physics measurements and units kinds of units fundamental quantities standardized measurement

The SI unit of specific latent heat is 

  1. $Jkg^{-1}K^{-1}$
  2. $J^{0}K^{-1}$
  3. $J kg^{-1}$
  4. $J kgK^{-1}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The specific latent heat of a substance is the quantity of heat energy required to change the state of a unit mass of a substance.

${E} _{L}= ml$

here ${E} _{L}$ is the heat transferred, in joules,m is the mass, in kilograms, and l is the latent heat in joules per kilogram.

The SI unit for specific latent heat is $J{kg}^{-1}$.