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 mutual inductance electromagnetic induction electromagnetic induction and alternating currents physics

Give the MKS units for the following quantities.
Magnetic Induction.

  1. Weber$/m^3$.
  2. Weber$/m^2$.
  3. Weber$/m^4$.
  4. Weber$/m^5$.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

B. $Weber/m^2$

The term magnetic flux density refers to the fact that B is magnetic flux per unit surface. This relationship is based on Faraday's law of magnetic induction.
The SI unit measuring the strength of B is T(Tesla= $Weber/m^2$)

Multiple choice

The SI unit of pressure is the?

  1. Bernoulli

  2. Pascal

  3. Boyle

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

The Pascal (Pa) is the SI unit for pressure, defined as one Newton per square meter.

Multiple choice

the basic unit of a chemical element

  1. atom

  2. molecule

  3. substance

  4. heat
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An atom is the smallest unit of an element that retains the chemical properties of that element.

Multiple choice physics dynamics - explaining motion physical quantities motion and measurement units - definitions and systems

In particular system of unit, if the unit of mass becomes twice and that of time becomes half, then $8$ Joules will be written as _______ units of work

  1. $16$
  2. $1$
  3. $4$
  4. $64$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The unit of work is $kg\ m^2/s^2$.

$8Joule=\dfrac { 8M{ L }^{ 2 } }{ { T }^{ 2 } }$

$ =\dfrac { 8(1kg){ (1m) }^{ 2 } }{ { (1s) }^{ 2 } } $

On doubling the unit of mass and unit of time is halved:
$=\cfrac { 8(2\quad unit\quad of\quad mass){ (1m) }^{ 2 } }{ { \left( \frac { 1 }{ 2 } unit\quad of\quad time \right)  }^{ 2 } }$

$ =\dfrac { 8\times 2 }{ { \left( \frac { 1 }{ 2 }  \right)  }^{ 2 } } units\quad of\quad work\\ =64\ units\quad of\quad work.$

Multiple choice physics gravitational fields representing a gravitational field gravitational field circular motion and gravitation

Which of the following represents the unit for gravitational intensity?

  1. N
  2. $kgm^{-2}$
  3. $Nkg^{-1}$
  4. $ms^{-3}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Gravitational intensity is nothing but the acceleration due to gravity $=g=F _g/m$


Now we know that the SI unit of $F _g$ is $Newton(N) $ and that of $m$ is $kg$
So SI unit of $g=N/kg=Nkg^{-1}$ or $m/s^2$ 

Hence correct answer is option $C $ 

Multiple choice physics gravitational fields representing a gravitational field gravitational field circular motion and gravitation

The unit of (V) Gravitational Potential is

  1. $\dfrac{\text{Joule}}{kg}$
  2. $\text{Joule}$
  3. $\dfrac{\text{Joule}}{s}$
  4. $\dfrac{kg}{\text{Joule}}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Gravitational potential is defined as the Gravitational energy per unit mass of the object on the planet. Unit of energy is always joule in SI units. Hence that of potential will be Joule/kg.

Multiple choice stefan's law black body radiation heat transfer thermal properties physics

Match the physical quantities given in Column I with their SI units given in Cloumn II :

Column-I Column-II
(a) Thermal conductivity (p) Wm$^{-2}$K$^{-4}$
(b) Stefans constant (q) m-K
(c) Wiens constant (r) J kg$^{-1}$K$^{-1}$
(d) Specific heat (s)Wm$^{-1}$K$^{-1}$

  1. a-s, b-p, c-q, d-r

  2. a-s, b-p, c-r, d-q

  3. a-s, b-r, c-p, d-q

  4. a-r, b-s, c-p, d-q
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Thermal conductivity =$\dfrac{Watt}{Metre.Kelvin}$

Stefan's constant $=5.64\times$ ${10}^{-8}$$\dfrac { w }{ { m }^{ 2 }{ K }^{4}}$

Wien's constant $={\lambda}{\theta}={constant}={Metre}  {Kelvin}$

Specific heat $=\dfrac{Joule} {{Kg}  {Kelvin}}$

Multiple choice

What is the fundamental unit of information in quantum mechanics?

  1. Qubit

  2. Bit

  3. Byte

  4. Electron
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In quantum mechanics, the fundamental unit of information is the qubit, which can exist in a superposition of states, unlike the classical bit that can only be in one state at a time.

Multiple choice

The SI unit of force is the:

  1. Newton (N)

  2. Kilogram (kg)

  3. Meter (m)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The SI unit of force is the Newton (N), named after Sir Isaac Newton. It is defined as the force required to accelerate a mass of one kilogram at a rate of one meter per second squared.

Multiple choice

What is the SI unit of temperature?

  1. Fahrenheit

  2. Celsius

  3. Kelvin

  4. Rankine
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The SI unit of temperature is Kelvin.

Multiple choice

What is the SI unit of viscosity?

  1. Pascal-second (Pa·s)

  2. Newton-second (N·s)

  3. Poise (P)

  4. Stokes (St)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The SI unit of viscosity is the pascal-second (Pa·s). It is defined as the shear stress required to produce a unit velocity gradient in a fluid.

Multiple choice

What is the SI unit of conductivity?

  1. Siemens per meter (S/m)

  2. Ohms per meter (Ω/m)

  3. Farads per meter (F/m)

  4. Henrys per meter (H/m)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The SI unit of conductivity is Siemens per meter (S/m).

Multiple choice

What is the fundamental unit of measurement in photometry?

  1. Candela

  2. Lumen

  3. Lux

  4. Watt
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The candela is the SI unit of luminous intensity, which is the measure of the luminous power emitted by a light source in a particular direction.

Multiple choice

What is the fundamental unit of measurement in astrometry?

  1. Light-year

  2. Parsec

  3. Astronomical unit

  4. Degree
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The degree is the fundamental unit of measurement in astrometry, representing 1/360th of a circle.