1. In a bridge rectifier circuit the rms value of input ac voltage is 10V. The PIV across each diode is (a) 7.07V (b) 14.14V (c) 10V (d) 28.28v 2. The coupling capacitor in amplifier circuits (a) Affects dc biasing (b) Does not affect dc biasing. (c) Affects dc biasing to some extent (d) Both
1. A 400 W carrier is modulated to a depth of 75 percent. The total power in modulated wave will be (a) 38.5 W (b) 400 W (c) 512.5 W (d) 615.5 W 2. In a PCM system, if we increase the quantization levels from 2 to 8, how do the relative bandwidth requirements vary?
1. In a flux meter, the controlling torque is (a) produced by weight attached to the moving coil (b) produced by spring (c) provided by cross coil mechanism (d) not provided by all 2. Moving coil galvanometer is made into a dc ammeter by connecting (a) a low resistance in series with the meter (b)
1. In case of RC driving point function (a) ZRC cannot have a pole at infinity (b) ZRC cannot have a pole at origin (c) YRC cannot have a pole at infinity (d) ZRC and YRC are constant or zero at infinity 2. A Hurwitz polynomial has (a) zeros only in the left half plane
1. The temperature co-efficient of resistance of a semiconductor is (a) +ve (b) –ve (c) Zero (d) very high 2. In an unbiased P-N junction, thickness of depletion layer is of the order of (a) 0.005μm (b) 0.5 μm (c) 5 μm (d) 1nm 3. JFET can operate in (a) depletion mode and enhancement mode
1. Find the wrong statement: specific heat of a material is (a) Constant (b) heat capacity per unit mass (c) extrinsic property (d) of units as Joule/Kg-K 2. Metals have thermal conductivities in the range of (a) < 1 (b) 1-5 (c) 5-25 (d) 20-400 3. For carbon resistors what is the color for 5?
1. Magnetic amplifier is used for amplification of (a) Voltage (b) Power (c) Current (d) frequency 2. In position control system the device, used for providing rate-feedback voltage is (a) Potentiometer (b) synchro-transmitter (c) synchro- transformer (d) tacho-generator 3. Which of the following is used to obtain output position in a position control system? (a)
1. Which of the following can be used as Parallel to series converter? (a) Decoder (b) Counter (c) Encoder (d) multiplexer 2. A Johnson counter with 5 flips flops will have (a) 5 states (b) 10 states (c) 32 states (d) ∞ states 3. A 4 bit ripple counter uses flip flops with propagation delay
1. A CE amplifier has re=6Ω, β=100. The input impedance is (a) 6Ω (b) 98Ω (c) 100Ω (d) 600Ω 2. The most commonly used bias in BJT amplifier circuit is (a) voltage divider bias (b) emitter bias (c) collector bias (d) collector feedback bias 3. In a commercially available good power supply the voltage regulation
1. The maximum theoretical efficiency for class A amplifier is (a) 12.5% (b) 25 % (c) 50% (d) 75% 2. If it is desired to have low output impedance in an amplifier circuit then we should use (a) common collector circuit (b) common base circuit (c) common emitter circuit (d) either (b) or (c) 3.
