Physics

# The flux of magnetic field through a closed conducting loop changes with time according to the equation,$\Phi ={ at }^{ 2 }+bt+c$.$(a)$ Write the $SI$ units of $a,b$ and $c$ $(b)$ If the magnitudes of $a,b$ and $c$ are $0\cdot 20, 0.40$ and $0.60$ respectively, find the including emf at $t=2\ s$.

##### SOLUTION
Given:
$\Phi ={ at }^{ 2 }+bt+c$
Same dimensional quantity can be added, subtracted and equated.
(a) $a=\left[ \cfrac { \phi }{ { t }^{ 2 } } \right] =\left[ \cfrac { \phi /t }{ t } \right] =\cfrac { volt }{ sec } ; \ \ \ b=\left[ \cfrac { \phi }{ { t }^{ } } \right] =volt; \ \ \ c=\left[ \phi \right] =Weber$

(b) $a=0.2,b=0.4,c=0.6,t=2s$
$\quad E=\cfrac { d\phi }{ { dt }^{ } } =2at+b=2\times 0.2\times 2+0.4=1.2volt$

You're just one step away

Subjective Medium Published on 18th 08, 2020
Questions 244531
Subjects 8
Chapters 125
Enrolled Students 204

#### Realted Questions

Q1 Single Correct Medium
The relation between force 'F' and density 'd' is $F=\displaystyle\frac{x}{\sqrt d}$. The dimensions of $x$ are
• A. $\displaystyle [L^{-1{/2}}M^{3{/2}}T^{-2}]$
• B. $\displaystyle [L^{-1{/2}}M^{1{/2}}T^{-2}]$
• C. $\displaystyle [L^{-1}M^{3{/2}}T^{-2}]$
• D. $\displaystyle [L^{-1}M^{1{/2}}T^{-2}]$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q2 Single Correct Medium
The critical velocity $v$ of a body depends on the coefficient of viscosity $\eta$, the density $d$ and radius of the drop $r$. If $K$ is a dimensionless constant then $v$ is equal to :
• A. $\dfrac { K\eta d }{ r }$
• B. $\dfrac { K d }{\eta r }$
• C. $\dfrac { K\eta }{d r }$
• D. $\dfrac { Kr}{\eta d }$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q3 Multiple Correct Medium
Which of the statements are correct?
• A. Unit of work is $kgm^2s^{-2}$
• B. Unit of force is $kgms^{-2}$
• C. Unit of work is $kgms^{-2}$
• D. Unit of force is $kgm^2s^{-2}$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q4 Single Correct Medium
While measuring the diameter of a wire by screw gauge, three readings were taken are $1.002$ cm, $1.004$ cm and $1.006$ cm. The absolute error in the third reading is?
• A. $0.002$ cm
• B. $0.004$ cm
• C. Zero
• D. $1.002$ cm

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q5 Subjective Medium
The distance of a galaxy is $56 \times10^{25}m$. Assume the speed of light to be $3\times10^8 m s^{-1}$. Express order of magnitude of time taken by light travelled to the galaxy.

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020