Basic Electrical Engineering _B div 2022

if 110V is applied across a 220V, 100W bulb the power consumed by it will be

• 100W

• 50W

• 25W

• 12.5W

Voltage drop across 14.5 Ω resistor in figure

• 29 V

• 30.5 V

• 14 V

• 18 V

Three resistances of 5Ω, 10Ω & 20Ω are connected in parallel. Find their equivalent resistance.

• 20/7Ω
• 7/20Ω
• 5Ω
• 20Ω

The phase angle difference between current and voltage is 90^o, the power will be ________

• minimum

• maximum

• zero

• VI

The form factor is the ratio of

• peak value to r.m.s. value

• r.m.s. value to average value

• average value to r.m.s. value

• none of the above

The power factor of a purely resistive circuit is

• zero

• unity

• lagging

• leading

The formula for Apperent Power in 3-phase circuit is________

• 3.VL.IL
• √3.VL.IL.cosø
• √3.VL.IL
• VL.IL

how many electrical degrees are phases displaced

• 30

• 60

• 90

• 120

This picture is an example of a ________________.

• Motor

• Generator

• Step-up transformer

• Step-down transformer

The efficiency of a transformer will be maximum when ?

• copper losses = hysteresis losses

• hysteresis losses = eddy current losses

• eddy current losses = copper losses

• copper losses = iron losses