Elec 03-06 DC Ciruits

If a resistance to which a constant voltage is applied is halved, what power dissipation will result?

• Doubled
• Halved
• Stays the same
• Quadrupled

If the reference point is changed to the earth point then any voltage taken w.r.t. the earth is known as

• Absolute potential
• Earth ground
• Relative voltage
• Absolute point

What is the significance of connecting loads in parallel?

• It makes power consumption less
• It provides greater efficiency
• It increases the safety factor
• It allows independent operations of loads

Which of the following safety rules should be observed while working on live electric circuit?

• Keep yourself well insulated from earth ground
• When making measurements in a live circuit place one hand behind your back or in your pocket
• Make resistance measurements only in a live circuit
• Both A and B

The hot resistance of an incandescent lamp is about _____ times its cold resistance.

• 10
• 50
• 5
• 100

If a resistor in a series circuit is shorted, the series current, I,

• decreases
• stays the same
• increases
• drops to zero

The equivalent wye element of 3 equal resistors each equal to R and connected in delta is

• R
• R/3
• 3/2 R
• 3R

A wire with a smaller cross-sectional area will produce:

• less heat
• more conductance
• less resistance
• more heat

Halving the cross-sectional area of a conductor will:

• Not affect the resistance
• Quarter the resistance
• Half the resistance
• Double the resistance

In Norton’s Theorem, the short circuit current is obtained by

• opening the load terminals
• shorting the load terminals
• opening the voltage source
• shorting the voltage source