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of transformers are used for high power.
A) Shell type B) Berry type C) CT type D) Core type
Moving coil instrument works on the effect of
A) Electromagnetic effect B) Heating effect
C) Chemical effect D) Electrostatic effect

In an induction motor, if the flux density of rotor is reduced to half of its normal value,
the torque will

A) Reduce to half B) Reduce to one fourth
C) Increase three folds D) Remain unchanged

In a transformer minimum voltage regulation occurs when the power factor of the
load is

A) lagging B) leading C) 0.8 D) unity

A dynamometer type wattmeter has

A) Non-linear scale B) Logarithmic scale

C) Square law scale D) Uniform scale

Vaccum cleaners generally use motor.

A) universal B) shaded pole C) hysteresis D) reluctance

Which is the cause for deterioration of transformer oil ?
A) Insufficient cooling
B) Long time and continuous use
C) Due to atmosphere air come into contact with oil
)

D) Due to over load

The laws of illumination are applicable

A) To a point source of light in the absence of reflecting surfaces

B) To a point source of light in the presence of reflecting surfaces

C) Irrespective of whether the source of light is a point source or extended source
D) Both A) and B)

A total of 20 fluorescent lamps are required to illuminate a surface of 100m? with an
illumination of 200 lux, taking coefficient of utilisation as 0.5 and depreciation factor
as 1.25. Find out the lumen output of the lamp.

A) 2000 lumens B) 2500 lumens C) 625 lumens D) 1600 lumens