For a moving coil galvanometer,the deflection | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The torque acting on the coil of a moving coil galvanometer is given by $	au = NiAB$,where $N$ is the number of turns,$i$ is the current,$A$ is t

Vedclass · Accepted Answer

$1$

Vedclass · Answer

(B) The torque acting on the coil of a moving coil galvanometer is given by $	au = NiAB$,where $N$ is the number of turns,$i$ is the current,$A$ is the area,and $B$ is the magnetic field.The restoring torque provided by the suspension wire is $	au = K	heta$,where $K$ is the torsional constant and $	heta$ is the deflection.Equating the two torques: $NiAB = K	heta$.Rearranging for the area $A$: $A = \frac{K	heta}{NiB}$.Given values:$K = 4.0 	imes 10^{-5}\,Nm\,rad^{-1}$$	heta = 0.05\,rad$$N = 200$$i = 10\,mA = 10 	imes 10^{-3}\,A = 0.01\,A$$B = 0.01\,T$Substituting the values:$A = \frac{4.0 	imes 10^{-5} 	imes 0.05}{200 	imes 0.01 	imes 0.01}$$A = \frac{2.0 	imes 10^{-6}}{0.02} = 1.0 	imes 10^{-4}\,m^2$.Since $1\,m^2 = 10^4\,cm^2$,we have:$A = 1.0 	imes 10^{-4} 	imes 10^4\,cm^2 = 1\,cm^2$.

Similar Questions

If only $1 \%$ of the total current is passed through a galvanometer of resistance $G$,then the resistance of the shunt is:

The percentage error in the reading of the voltmeter in the figure shown here is nearly ............ $\%$

$A$ moving coil galvanometer has $48$ turns and the area of the coil is $4 \times 10^{-2} \, m^2$. If the magnetic field is $0.2 \, T$,then to increase the current sensitivity by $25\%$ without changing the area $(A)$ and the magnetic field $(B)$,the number of turns should become:

Voltmeters $V_1$ and $V_2$ are connected in series across a $D.C.$ line. $V_1$ reads $80 \, V$ and has a resistance per volt of $200 \, \Omega/V$. $V_2$ has a total resistance of $32 \, k\Omega$. The line voltage is ............. (in $V$)

Derive the expression for the shunt resistance required to increase the current-measuring capacity of a galvanometer by a factor of $n$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module