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 physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

Name the physical quantity(s) which is(are) measured in the $nm$.

  1. Length

  2. Density

  3. Volume

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

Nanometre or $nm$ is a unit of length in the metric system. $1\ nm=10^{-9}\ m$.

The nanometre is often used to express dimensions on an atomic scale: the diameter of a helium atom, for example, is about $0.1\ nm$, and that of a ribosome is about $20\ nm$. The nanometre is also commonly used to specify the wavelength of electromagnetic radiation near the visible part of the spectrum: visible light ranges from around $400$ to $700\ nm$.

Multiple choice physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

The measure of amount of matter contained inside a body is called its ___________.

  1. Weight

  2. Mass

  3. Area

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Mass is the amount of matter contained inside a body and it remains constant irrespective of the change in its location

Mass is a measure of amount of matter contained inside body.

Multiple choice physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

It has long been an objective in metrology to define the kilogram in terms of a fundamental constant, in the same way that the ____________________ is now defined in terms of the speed of light. 

  1. centimetre

  2. metre

  3. decimetre

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Metre is the SI unit used for measuring the distance which is defined taking speed of light as a reference.

Multiple choice physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

The kilogram, originally defined as the mass of ___________________at the temperature of maximum density, was known as the Kilogram of the Archives.

  1. one cubic decimeter of gasoline

  2. one cubic decimeter of water

  3. one cubic decameter of water

  4. one square decameter of water
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The kilogram, defined as the mass of one cubic decimeter of water at $4^o C$ is known as kilogram of the Archives.

Multiple choice physics physical quantities and measurement measurement of small and large distances measurement of distance unit of fundamental quantities

The kilogram is the SI base unit of mass and is equal to the mass of the international prototype of the kilogram , a ___________standard that is kept at the International Bureau of Weights and Measures (BIPM) .

  1. platinum-iridium

  2. platinum

  3. iridium

  4. all of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Platinum-iridium is the standard that is kept at the International Bureau of Weights and Measures (BPIM).

Multiple choice intensity and loudness waves physics

Decibel is the unit of physical quantity used for : 

  1. The speed of light

  2. The intensity of heat

  3. The intensity of sound

  4. The frequency of radiowaves
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Answer is C.

The intensity or loudness of a sound depends upon the extent to which the sounding body vibrates, i.e., the amplitude of vibration. A sound is louder as the amplitude of vibration is greater, and the intensity decreases as the distance from the source increases. Loudness or intensity of sound is measured in units called decibels. 

Multiple choice intensity and loudness waves physics

S. I. unit of intensity of sound is:

  1. joule s$^{-1}$ m$^{-2}$
  2. watt m$^{-2}$
  3. joule s/m$^2$

  4. both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In S. I. unit of intensity of sound is
joule s$^{-1}$ m$^{-2}$ or watt m$^{-2}$
Intensity = sound energy/time $\times$ area