Q.281 Two heaters, rated at 500W 250 V each are connected in series across a 250v, 50 Hz mains. The total power drawn from the supply wound be_____watt.
A. 500
B. 250
C. 1000
D. 125
Ans.: B
Q.282 The RMS value of the voltage u(t) = 3+ 4cos(3t) is:
A. 5
B. 4.12
C. 7
D. 3+2(1.41)
Ans.: B
Q.283 The instantaneous value of power in purely inductive circuit is
A. constant
B. changing
C. zero
D. none of this
Ans.: B
Q.284 In the Standard B-H curve X-axis and Y-axis intersects respectively represents
A. residual magnetism and coercive force
B. Coercive force and residual magnetism
C. Hysteresis loss and Flux
D. Flux and MMF
Ans.: A
Q.285 Two watt meter method for 3 phase circuit is preferred over other methods because
A. Pf of the load can also be estimated
B. it can be used for star or delta connected load
C. it can be used for balanced of unbalanced load
D. all are correct
Ans.: D
Q.286 Laplace transforms is used for
A. Finding transfer function of any system
B. converting non linear equation to linear equation
C. converting differential equation to algebraic equation
D. for finding initial condition in a system
Ans.: C
Q.287 “Overshoot” in a time response of control systems is indication of
A. final value of the output
B. measure of relative stability
C. steady state solution
D. none of this
Ans.: B
Q.288 Root Locus is locus of the …
A. open loop poles to open loop zero
B. open loop zeros to close poles
C. close loop poles to close loop zeros
D. close loop poles
Ans.: D
Q.289 Which of the following is the most likely reason for large overshoot in a control system?
A. high gain in a system
B. presence of dead time delay
C. high positive correcting torque
D. high retarding torque
Ans.: C
Q.290 When the load is suddenly increased in the receiving end of the system, the phase shift will
A. not affected
B. increase
C. decrease
D. remains same
Ans.: B
Q.291 In G-S method of power flow problem, the number of iterations…
A. depends on no of buses
B. depends on tolerance
C. depends on voltage controls
D. remains fixed
Ans.: B
Q.292 In load flow analysis, the load at the bus is represented as
A. a voltage dependent impedance at the bus
B. a constant impedance connected at the bus
C. a constant current drawn from the bus
D. none of this
Ans.: D
Q.293 The constrains that are to be met with while solving PC problem are
A. Spinning reserve
B. Minimum up time
C. Minimum down time
D. all are correct
Ans.: D
Q.294 100% string efficiency means
A. one of the insulators disc shorted
B. zero potential across each disc
C. non uniform potential distribution across each disc
D. Equal potential across each disc
Ans.: D
Q.295 Critical clearing time of a fault in a power system is related to
A. Reactive power limit
B. short circuit limit
C. Transient stability limit
D. Steady state limit
Ans.: C