1
GATE EE 2014 Set 3
Numerical
+1
-0
An $$LPF$$ wattmeter of power factor $$0.2$$ is having three voltage settings $$300V,$$ $$150V$$ and $$75V,$$ and two current settings $$5 A$$ and $$10A.$$ The full scale reading is $$150.$$ If the wattmeter is used with $$150V$$ voltage setting and $$10A$$ current setting, the multiplying factor of the wattmeter is __________.
2
GATE EE 2014 Set 2
Numerical
+1
-0
While measuring power of a three-phase balanced load by the two-wattmeter method, the readings are $$100$$ $$W$$ and $$250$$ $$W$$. The power factor of the load is ___________.
3
GATE EE 2012
+1
-0.3
For the circuit shown in the figure, the voltage and current expressions are
$$v\left( t \right) = {E_1}\sin \left( {\omega t} \right) + {E_3}\sin \left( {3\omega t} \right)$$ and
$$i\left( t \right) = {{\rm I}_1}\sin \left( {\omega t - {\varphi _1}} \right) + {{\rm I}_3}\sin \left( {3\omega t - {\varphi _3}} \right) + {{\rm I}_5}\sin \left( {5\omega t} \right)$$

The average power measured by the Wattmeter is

A
$${1 \over 2}{E_1}{{\rm I}_1}\cos {\phi _1}$$
B
$${1 \over 2}\left[ {{E_1}{{\rm I}_1}\cos {\phi _1} + {E_1}{{\rm I}_3}\cos {\phi _3} + {E_1}{{\rm I}_5}} \right]$$
C
$${1 \over 2}\left[ {{E_1}{{\rm I}_1}\cos {\phi _1} + {E_3}{{\rm I}_3}\cos {\phi _3}} \right]$$
D
$${1 \over 2}\left[ {{E_1}{{\rm I}_1}\cos {\phi _1} + {E_3}{{\rm I}_1}\cos {\phi _1}} \right]$$
4
GATE EE 2011
+1
-0.3
Consider the following statement:
(i) The compensating coil of a low power factor wattmeter compensates the effect of the impedance of the current coil.
(ii) The compensating coil of a low power factor wattmeter compensates the effect of the impedance of the voltage coil circuit.
A
(i) is true but (ii) is false
B
(i) is false but (ii) is true
C
both (i) and (ii) are true
D
both (i) and (ii) are false
EXAM MAP
Medical
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