Tag: physics

Quizzes (598) Questions (13441)

Questions Related to physics

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

In the eqn. $\left (P+\dfrac {a}{V^2}\right )(V-b)=$ constant, the unit of $a$ is

  1. $dyne\times cm^5$
  2. $dyne\times cm^4$
  3. $dyne/cm^3$
  4. $dyne\times cm^2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Units of both $P $ and $ \dfrac {a}{V^2}$ must be same.
So, $\dfrac {a}{V^2}=P$  $\implies   a=PV^2$ 

Since unit of $P$ is $dyne \ cm^{-2}$ and that of $V$ is $cm^3$.
$\therefore$ Unit of a is  $\dfrac {dyne}{cm^2}(cm^3)^2=dyne\times cm^4$

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

Which of the following physical quantity is different form others ?

  1. Displacement

  2. Velocity

  3. Force

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

Displacement, force, and velocity are vector quantities as they require direction as well as the magnitude for their representation but the kinetic energy is a scalar quantity as it does not require direction for its representation.

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

Write the SI unit of the physical quantity having following dimensional formula
$\displaystyle [{ M }^{ 0 }{ L }^{ 2 }{ T }^{ -2 }{ K }^{ -1 }]$.

  1. $\displaystyle {m} { kg }^{ 2 }{ K }^{ -1 }$
  2. $\displaystyle {m} ^{2} { kg }^{ 2 }{ T }^{ -1 }$
  3. $\displaystyle {m} ^{2} { s }^{ -2 }{ K }^{ -1 }$
  4. $\displaystyle {m} ^{2} { kg }^{ 2 }{ K }^{ -1 }$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
SI unit of $M$ is $kg$, that of $L$ is $m$, $T$ is $s$ and temperature (K) is $K$.

So, SI unit of $[M^0L^2T^{-2}K^{-1}]$ is  $m^2s^{-2}K^{-1}$.
Multiple choice physics measurement of physical quantities kinds of units fundamental quantities standardized measurement

Dimensional analysis is the analysis of the relationships between different physical quantities by 

  1. identifying their fundamental dimensions

  2. units of measure

  3. tracking these dimensions as calculations or comparisons are performed.

  4. All of the above

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Dimensional analysis establishes the relation between the physical quantities by comparing the different quantities using their fundamental dimensions.

The dimensional analysis also makes use of the units to measure different quantities and the dimensional analysis is also helpful in performing several calculations.