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Multiple choice physics measurements and units summary of si units fundamental quantities system of units

The dimensional formula for magnetic flux is:

  1. $(ML^2T^{-2}A^{-1})$

  2. $(ML^3T^{-2}A^{-2})$

  3. $(M^0L^{-2}T^{2}A^{-2})$

  4. $(ML^2T^{-1}A^{2})$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The magnetic flux if given by

$\phi=BAcos\theta$
If $cos\theta=1$
The maximum magnetic flux, $\phi=BA$. . . . . .(1)
where, $B=$ magnetic field
$A=area$ 
The dimensional formula for magnetic field,
$F=qvB$
where, $v=$ velocity
$q=$ charge,
$B=$ magnetic field
$[B]=\dfrac{M^1 L^1T^{-2}}{[A^1 T^1][L^1T^{-1}]}$
$[B]=[M^1L^0T^{-2}A^{-1}]$
for area, $[A]=[M^0 L^2 T^0]$
The dimensional formula for magnetic flux,
$[\phi]=[M^1L^0 T^{-2}A^{-1}].[M^0L^2T^0]$
$[\phi]=[M^1L^2T^{-2}A^{-1}]$
The correct option is A.

Multiple choice physics measurements and units summary of si units fundamental quantities system of units

The SI unit of gravitational potential is :

  1. Joule/kg

  2. Joule$^2$/kg

  3. kg/Joule

  4. Joule/kg$^2 $
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The gravitational potential at a point is the potential energy associated with a unit mass due to its position in the gravitational field of another body. Gravitational potential is the amount of work done in bringing a body of unit mass from infinity to that point.
Gravitational potential (V) $=\dfrac{Work done}{Mass}=\dfrac{W}{m}$
Gravitational potential  is a scalar quantity and the  SI unit is $J/kg$. 

Multiple choice physics measurements and units summary of si units fundamental quantities system of units

The SI unit of $ \dfrac{1}{2 \pi \sqrt{LC}}$ is equivalent to that of :

  1. time period

  2. frequency

  3. wavelength

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

The angular frequency of current oscillations in an LC circuit is given by $\omega =\dfrac{1}{\sqrt {LC}}$ and $\omega = 2\pi f$.
$\Rightarrow f= \dfrac{1}{2\pi \sqrt{LC}}$ and the unit is equivalent to that of frequency.