41. Which will draw least current**a. 40 W lamp **

b. 40-W tube light

c. 40 W induction motor

42. The instantaneous value of current i at t = 0.35 ms will be

a. 10.1 mA**b. 20.5 mA**

c. 205 mA

d. 101 mA

43. What value of dc voltage will produce the same average power as 150 V peak sine wave

a. 144 V

b. 121 V

c. 111 V**d. 106 V**

44. What current will an ammeter show when connected in series with a 32 ohm load that is dissipating a peak power of 288 W?

a. 1.06**b. 2.12 A**

c. 4.24 A

d. 8.48 A

45. A 160 W soldering iron is operated from the 60 Hz power line. The resistance of the soldering iron is

a. 10 ohms

b. 25.5 ohms

c. 51.5 ohms**d. 75.6 ohms**

46. A certain 1-KHz sine wave reaches – 70 V at t = 0.6 ms . The peak value of this sine wave will be

a. 100 V

b. 114 V

c. 141.4 V**d. 118 V**

47. In a.c circuits the a.c meters measure **a. r.m.s values **

b. peak values

c. mean value

d. mean square value

48. Radio frequency choke is air – cored to

a. keep frequency low

b. keep frequency high**c. keep inductive reactance low**

d. keep inductance reactance high

49. Hot wire ammeters are used for measuring

a. both a.c and d.c**b. only a.c**

c. only d.c

d. neither a.c nor d.c

50. A choke coil is used for controlling current in an**a. a.c circuit only**

b. d.c circuit only

c. both a.c and d.c circuits

d. Integrated circuits