1
GATE EE 1999
MCQ (Single Correct Answer)
+2
-0.6
A current of $$\left[ {2 + \sqrt 2 \sin \left( {314t + 30} \right) + 2\sqrt 2 \cos \left( {952t + 45} \right)} \right]$$ is measured with a thermocouple type. $$5A$$ full scale, class $$1$$ meter. The meter reading would like in the range,
A
$$5A \pm 1\% $$
B
$$\left( {2 + 3\sqrt 2 } \right)A \pm 1\% $$
C
$$3A \pm 1.7\% $$
D
$$2A \pm 0.5\% $$
2
GATE EE 1999
Subjective
+5
-0
Two single phase transformers $$A$$ and $$B$$ have the following parameters.
Transformer $$A$$: $$400V/200V,$$ $$10$$ $$kVA,$$ percentage resistance and percentage reactance are $$3\% $$ and $$4\% $$ respectively.
Transformer B: $$5$$ $$kVA,$$ $$400V/200V,$$ percentage resistance and percentage reactance are $$4\% $$ and $$3\% $$ respectively.
These two transformers are connected in parallel and they share a common load of $$12$$ $$kW$$ at a power factor of $$0.8$$ lag. Determine the active and reactive power delivered by transformer $$A.$$
3
GATE EE 1999
Subjective
+5
-0
A separately excited $$DC$$ shunt motor is driving a fan load whose torque is proportional to the square of the speed. When $$100$$ $$V$$ are applied to the motor, the current taken by the motor is $$8$$ $$A,$$ with the speed being $$500$$ $$rpm.$$ At what applied voltage does the speed reach $$750$$ $$rpm$$ and then what is the current drawn by the armature? Assume the armature circuit resistance to be $$1\,\,\,\Omega .$$ Neglect brush drop and mechanical losses.
4
GATE EE 1999
MCQ (Single Correct Answer)
+1
-0.3
The following starting method for an induction motor is inferior view of the poor starting torque per ampere of the line current drawn:
A
Direct line starting
B
Auto transformer method of starting
C
Series inductor method of starting
D
Star-Delta method of starting