Q.1 The charging and discharging of a RC combination by a battery and switch is seen on a CRO. The waveform will be
(a) a sawtooth
(b) square pulses
(c) sawtooth of amplitudeVc
(d) square pulses of amplitude Vr+Vc
ans. (d)
Q.2 Hystersis losses
(a) are caused by high frequency a.c current
(b) generally increase with direct current in a coil
(c) can't be produced in an iron core because it is a conductor
(d) none of these
ans (a)
Q.3 intrinsic impedance of free space is given as
(a) 75 ohm
(b) 73 ohm
(c) 377 ohm
(d) 300 ohm
ans (c)