Sunday, January 4, 2015

ELECTRICAL CIRCUITS OBJECTIVE BITS -2



 1)   When a resistor R is connected to a current source, it consumes a power of 18W. When the same R is connected to a voltage source having same magnitude as the current source, the power absorbed by R is 4.5W. The magnitude of the current source & value of R are
a) Root18 A & 1            b) 3,2             c) 1,18                       d) 6, 0.5                            Ans: (b)

2)     If v, w, q stand for voltage, energy & charge, the v can be expressed as

        a) v = dq / dw                  b) v = dw/ dq            c) dv = dw/ dq        d) dv= dq / dw. Ans: (b)

3)      The phase of even symmetric signal is

         a) + 90deg        b) - 90deg                c) 0deg      d) 0deg  or 180deg                       Ans: (d)

4)     A coil of resistor of 5ohms  and inductance 0.4 H is connected to a 50 V d.c supply. The energy             stored in the field is

a) 10 joules                  b) 20 joules           c) 40 joules           d) 80 joules               Ans:(b)

5)   Consider the following units:
1) sec-1 2) rad2 sec-2 3)sec 4) ohm, the units of R/L, 1 / LC, CR and sqt (L / C) are respectively.
a) 1,2,4 and 3 b) 3,2,1 and 4 c) 2,4,1 and 3 d) 1,2,3 and 4                                    Ans:(d)

6)  An ideal constant voltage source is connected in series with an ideal constant current source.               Considered together, the combination will be a
a) Constant voltage source b) constant current source c) constant voltage source and constant current source or a constant power source                                                           Ans: (b)

7)       A network contains only independent current sources and resistors. If the values of all the resistors are doubled, the values of the node voltage
a) will become half b) will remain unchanged c) will become double
d) cannot be determined unless the circuit configuration and the values of the resistors are known                                                                                                                              Ans: ©

8)   A network N is a dual of network N if
a) both of them have same mesh equations b) both of them have same node equations c) mesh equations of one are the node equations of the other d) KCL and KVL equations are the same
Ans: ©