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 chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

Name and unit are listed, which is NOT correctly written?

  1. Torr and pressure

  2. Mass and grams

  3. Heat energy and kilopascals

  4. Volume and milliliter

  5. Temperature and Kelvin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Unit of Heat energy is joule ($J$) not kilopascals. kilopascal is unit for pressure.


Hence the correct option is C.

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

SI unit of energy is: 

  1. $kg\, m^2 s^{-2}$
  2. $kg\, m^{-1} s^{2}$
  3. $kg\, m^2 s^{-1}$
  4. $kg\, m^2 s^{2}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The power required to do work by the application of force is energy.

Energy has same unit as that of work.
$\therefore$ S.I unit of Energy is $kgm^2 s^{-2}$

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

Which of the following is the correct value of $R$ in $SI$ units?

  1. $0.083$ $bar$ $dm^{3}K^{-1}mol^{-1}$
  2. $1.98\ cal K^{-1}mol^{-1}$
  3. $8.314\times 10^{7} erg K^{-1}mol^{-1}$
  4. $8.314 J\ K^{-1}mol^{-1}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$R$ is called as universal gas constant or molar gas constant.

              $R=0.0821\quad L\quad atm\quad { mol }^{ -1 }{ k }^{ -1 }\ R=0.0831\quad { dm }^{ 3 }bar\quad { mol }^{ -1 }{ k }^{ -1 }\ R=8.314\quad J\quad { mol }^{ -1 }{ k }^{ -1 }\ R=8.314\times { 10 }^{ 7 }erg\quad { mol }^{ -1 }{ k }^{ -1 }\ R=1.98\quad Cal\quad { mol }^{ -1 }{ k }^{ -1 }$
The $S.I$ units of molar gas constant $(R)$ is $J\quad { mol }^{ -1 }{ k }^{ -1 }$.
$\therefore \quad R=8.314\quad J\quad { mol }^{ -1 }{ k }^{ -1 }$ is the correct answer.

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

Electron Volt is a unit of:

  1. Potential difference

  2. Energy

  3. Charge

  4. Velocity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The electron volt (symbol eV; also written electronvolt) is a unit of energy equal to approximately 1.602$\times$10$^{−19}$ joule (SI unit J). 


By definition, it is the amount of energy gained by the charge of a single electron moved across an electric potential difference of one volt.

Hence, the correct option is $B$

Multiple choice chemistry matter around us measurement of properties effect of temperature and pressure on states of matter general introduction: importance and scope of chemistry

In the metric system, the prefix kilo-means :

  1. $10^0$
  2. $10^{-1}$
  3. $10^{-2}$
  4. $10^2$
  5. $10^3$
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

In the metric system, the prefix kilo-means $\displaystyle  10^3$. 
For example, 1 kg is equal to $\displaystyle  10^3 g$. 
1 km is equal to $\displaystyle  10^3 $ m.