Which method can be used for absolute measurement of resistances ?
Lorentz method
Releigh method
Wheatstone bridge method
Ohm’s law method
Wheatstone bridge method
Copper wire of certain length and resistance is drawn out to three times its length without change in volume the new resistance of wire becomes
9 times
unchanged
3 times
1/9 times
9 times
When resistance element of a heater fuses and then we reconnect it after removing a portion of it the power of the heater will
increase
remain constant
decrease
none of the above
increase
Three 6 ohm resistors are connected to form a triangle. What is the resistance between any two corners ?
8/3 Q
4 Q
3/2 Q
(b 6 Q
4 Q
Ohm’s law is not applicable to
semi-conductors
D.C. circuits
small resistors
high currents
semi-conductors
In an induction motor no-load the slip is generally
less than 1%
0.015
0.02
0.04
less than 1%
Slip ring motor is recommended where
high starting torque is needed
frequent starting stopping and reversing is required
speed control is required
all above features are required
all above features are required
If a 3-phase supply is given to the stator and rotor is short circuited rotor will move
in the opposite direction as the direction of the rotating field
in any direction depending upon phase squence of supply
in the same direction as the direction of the field
None of the above
in the same direction as the direction of the field
As load on an induction motor goes on increasing
its power factor goes on increasing up to full load and then it falls again
its power factor goes on increasing even after full load
its power factor remains constant
its power factor goes on decreasing
its power factor goes on increasing up to full load and then it falls again
In squirrel cage induction motors the rotor slots are usually given slight skew in order to
reduce magnetic hum
reduce eddy currents
reduce windage losses
reduce accumulation of dirt and dust
reduce magnetic hum
पोस्ट अच्छी लगी हो तो प्लीज नीचे दिए गए लिंक पर क्लिक कर शेयर जरुर करें
0 Comments