154238
Fleming's left and right hand rules are used in:
1 DC motor and AC generator
2 DC generator and $\mathrm{AC}$ motor
3 DC motor and DC generator
4 both rules are same, any one can be used
Explanation:
C Fleming's left and right hand rules are used in DC motor and DC generator. DC generator is a device which converts mechanical energy into electrical energy in form of DC. It employs Fleming's Right hand rule. DC motor is a device which converts electrical energy into mechanical energy it employs Fleming's left hand rule.
UPSEE - 2006
Magnetism and Matter
154257
A galvanometer has a resistance of $50 \Omega$. If a resistance of $1 \Omega$ is connected across its terminals, the total current flow through the galvanometer is $\left[I_{g}\right.$ represents the maximum current that can be passed through the galvanometer]
1 $42 I_{g}$
2 $53 \mathrm{I}_{\mathrm{g}}$
3 $46 I_{g}$
4 $51 I_{g}$
Explanation:
D Given, galvanometer resistance $(\mathrm{G})=50 \Omega$ Shunt $(\mathrm{S})=1 \Omega$ Max current through galvanometer resistance Galvanometer current $\left(\mathrm{I}_{\mathrm{g}}\right)=\mathrm{I}\left(\frac{\mathrm{S}}{\mathrm{G}+\mathrm{S}}\right)$ $I=\frac{I_{g}(G+S)}{S}=\frac{I_{g}(50+1)}{1}=51 I_{g}$
VITEEE-2006
Magnetism and Matter
154258
A certain current on passing through galvanometer produces a deflection of 100 divisions. When a shunt of one ohm is connected, the deflection reduces to 1 division. The galvanometer resistance is :
1 $100 \Omega$
2 $99 \Omega$
3 $10 \Omega$
4 $9.9 \Omega$
Explanation:
B Given, $\mathrm{I}=100 \mathrm{~A}, \mathrm{~S}=1 \Omega, \mathrm{G}=$ ? Galvanometer current $I_{g}=\frac{I S}{S+G}$ $1=\frac{100 \times 1}{1+G}$ $G=99 \Omega$
Karnataka CET-2008
Magnetism and Matter
154261
When the number of turns of the coil is doubled, the current sensitivity of a moving coil galvanometer is doubled whereas the voltage sensitivity of the galvanometer
1 remains the same
2 is halved
3 is doubled
4 is quadrupled
Explanation:
A Current Sensitivity $=\frac{\phi}{\mathrm{I}}=\frac{\mathrm{NAB}}{\mathrm{k}}$ Voltage sensitivity $=\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}$ Then, $\frac{\phi}{\mathrm{V}} \propto \frac{\mathrm{N}}{\mathrm{R}}$ If $\mathrm{N}=2 \mathrm{~N}$ then $\mathrm{R}=2 \mathrm{R}$ $\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}=\text { Remains constant }$
154238
Fleming's left and right hand rules are used in:
1 DC motor and AC generator
2 DC generator and $\mathrm{AC}$ motor
3 DC motor and DC generator
4 both rules are same, any one can be used
Explanation:
C Fleming's left and right hand rules are used in DC motor and DC generator. DC generator is a device which converts mechanical energy into electrical energy in form of DC. It employs Fleming's Right hand rule. DC motor is a device which converts electrical energy into mechanical energy it employs Fleming's left hand rule.
UPSEE - 2006
Magnetism and Matter
154257
A galvanometer has a resistance of $50 \Omega$. If a resistance of $1 \Omega$ is connected across its terminals, the total current flow through the galvanometer is $\left[I_{g}\right.$ represents the maximum current that can be passed through the galvanometer]
1 $42 I_{g}$
2 $53 \mathrm{I}_{\mathrm{g}}$
3 $46 I_{g}$
4 $51 I_{g}$
Explanation:
D Given, galvanometer resistance $(\mathrm{G})=50 \Omega$ Shunt $(\mathrm{S})=1 \Omega$ Max current through galvanometer resistance Galvanometer current $\left(\mathrm{I}_{\mathrm{g}}\right)=\mathrm{I}\left(\frac{\mathrm{S}}{\mathrm{G}+\mathrm{S}}\right)$ $I=\frac{I_{g}(G+S)}{S}=\frac{I_{g}(50+1)}{1}=51 I_{g}$
VITEEE-2006
Magnetism and Matter
154258
A certain current on passing through galvanometer produces a deflection of 100 divisions. When a shunt of one ohm is connected, the deflection reduces to 1 division. The galvanometer resistance is :
1 $100 \Omega$
2 $99 \Omega$
3 $10 \Omega$
4 $9.9 \Omega$
Explanation:
B Given, $\mathrm{I}=100 \mathrm{~A}, \mathrm{~S}=1 \Omega, \mathrm{G}=$ ? Galvanometer current $I_{g}=\frac{I S}{S+G}$ $1=\frac{100 \times 1}{1+G}$ $G=99 \Omega$
Karnataka CET-2008
Magnetism and Matter
154261
When the number of turns of the coil is doubled, the current sensitivity of a moving coil galvanometer is doubled whereas the voltage sensitivity of the galvanometer
1 remains the same
2 is halved
3 is doubled
4 is quadrupled
Explanation:
A Current Sensitivity $=\frac{\phi}{\mathrm{I}}=\frac{\mathrm{NAB}}{\mathrm{k}}$ Voltage sensitivity $=\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}$ Then, $\frac{\phi}{\mathrm{V}} \propto \frac{\mathrm{N}}{\mathrm{R}}$ If $\mathrm{N}=2 \mathrm{~N}$ then $\mathrm{R}=2 \mathrm{R}$ $\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}=\text { Remains constant }$
NEET Test Series from KOTA - 10 Papers In MS WORD
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Magnetism and Matter
154238
Fleming's left and right hand rules are used in:
1 DC motor and AC generator
2 DC generator and $\mathrm{AC}$ motor
3 DC motor and DC generator
4 both rules are same, any one can be used
Explanation:
C Fleming's left and right hand rules are used in DC motor and DC generator. DC generator is a device which converts mechanical energy into electrical energy in form of DC. It employs Fleming's Right hand rule. DC motor is a device which converts electrical energy into mechanical energy it employs Fleming's left hand rule.
UPSEE - 2006
Magnetism and Matter
154257
A galvanometer has a resistance of $50 \Omega$. If a resistance of $1 \Omega$ is connected across its terminals, the total current flow through the galvanometer is $\left[I_{g}\right.$ represents the maximum current that can be passed through the galvanometer]
1 $42 I_{g}$
2 $53 \mathrm{I}_{\mathrm{g}}$
3 $46 I_{g}$
4 $51 I_{g}$
Explanation:
D Given, galvanometer resistance $(\mathrm{G})=50 \Omega$ Shunt $(\mathrm{S})=1 \Omega$ Max current through galvanometer resistance Galvanometer current $\left(\mathrm{I}_{\mathrm{g}}\right)=\mathrm{I}\left(\frac{\mathrm{S}}{\mathrm{G}+\mathrm{S}}\right)$ $I=\frac{I_{g}(G+S)}{S}=\frac{I_{g}(50+1)}{1}=51 I_{g}$
VITEEE-2006
Magnetism and Matter
154258
A certain current on passing through galvanometer produces a deflection of 100 divisions. When a shunt of one ohm is connected, the deflection reduces to 1 division. The galvanometer resistance is :
1 $100 \Omega$
2 $99 \Omega$
3 $10 \Omega$
4 $9.9 \Omega$
Explanation:
B Given, $\mathrm{I}=100 \mathrm{~A}, \mathrm{~S}=1 \Omega, \mathrm{G}=$ ? Galvanometer current $I_{g}=\frac{I S}{S+G}$ $1=\frac{100 \times 1}{1+G}$ $G=99 \Omega$
Karnataka CET-2008
Magnetism and Matter
154261
When the number of turns of the coil is doubled, the current sensitivity of a moving coil galvanometer is doubled whereas the voltage sensitivity of the galvanometer
1 remains the same
2 is halved
3 is doubled
4 is quadrupled
Explanation:
A Current Sensitivity $=\frac{\phi}{\mathrm{I}}=\frac{\mathrm{NAB}}{\mathrm{k}}$ Voltage sensitivity $=\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}$ Then, $\frac{\phi}{\mathrm{V}} \propto \frac{\mathrm{N}}{\mathrm{R}}$ If $\mathrm{N}=2 \mathrm{~N}$ then $\mathrm{R}=2 \mathrm{R}$ $\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}=\text { Remains constant }$
154238
Fleming's left and right hand rules are used in:
1 DC motor and AC generator
2 DC generator and $\mathrm{AC}$ motor
3 DC motor and DC generator
4 both rules are same, any one can be used
Explanation:
C Fleming's left and right hand rules are used in DC motor and DC generator. DC generator is a device which converts mechanical energy into electrical energy in form of DC. It employs Fleming's Right hand rule. DC motor is a device which converts electrical energy into mechanical energy it employs Fleming's left hand rule.
UPSEE - 2006
Magnetism and Matter
154257
A galvanometer has a resistance of $50 \Omega$. If a resistance of $1 \Omega$ is connected across its terminals, the total current flow through the galvanometer is $\left[I_{g}\right.$ represents the maximum current that can be passed through the galvanometer]
1 $42 I_{g}$
2 $53 \mathrm{I}_{\mathrm{g}}$
3 $46 I_{g}$
4 $51 I_{g}$
Explanation:
D Given, galvanometer resistance $(\mathrm{G})=50 \Omega$ Shunt $(\mathrm{S})=1 \Omega$ Max current through galvanometer resistance Galvanometer current $\left(\mathrm{I}_{\mathrm{g}}\right)=\mathrm{I}\left(\frac{\mathrm{S}}{\mathrm{G}+\mathrm{S}}\right)$ $I=\frac{I_{g}(G+S)}{S}=\frac{I_{g}(50+1)}{1}=51 I_{g}$
VITEEE-2006
Magnetism and Matter
154258
A certain current on passing through galvanometer produces a deflection of 100 divisions. When a shunt of one ohm is connected, the deflection reduces to 1 division. The galvanometer resistance is :
1 $100 \Omega$
2 $99 \Omega$
3 $10 \Omega$
4 $9.9 \Omega$
Explanation:
B Given, $\mathrm{I}=100 \mathrm{~A}, \mathrm{~S}=1 \Omega, \mathrm{G}=$ ? Galvanometer current $I_{g}=\frac{I S}{S+G}$ $1=\frac{100 \times 1}{1+G}$ $G=99 \Omega$
Karnataka CET-2008
Magnetism and Matter
154261
When the number of turns of the coil is doubled, the current sensitivity of a moving coil galvanometer is doubled whereas the voltage sensitivity of the galvanometer
1 remains the same
2 is halved
3 is doubled
4 is quadrupled
Explanation:
A Current Sensitivity $=\frac{\phi}{\mathrm{I}}=\frac{\mathrm{NAB}}{\mathrm{k}}$ Voltage sensitivity $=\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}$ Then, $\frac{\phi}{\mathrm{V}} \propto \frac{\mathrm{N}}{\mathrm{R}}$ If $\mathrm{N}=2 \mathrm{~N}$ then $\mathrm{R}=2 \mathrm{R}$ $\frac{\phi}{\mathrm{V}}=\frac{\mathrm{NAB}}{\mathrm{kR}}=\text { Remains constant }$