Question: The effective channel length of a MOSFET in a saturation decreases with increase in___________?

• 1. Gate voltage
• 2. Drain voltage
• 3. Source voltage
• 4. Body voltage

Question: An n- channel JFET has IDSS=2mA,and Vp=-4v.Its transconductance gm=in mA/V)for an applied gate to source voltage VGS=-2v is___________?

• 1. 0.25
• 2. 0.5
• 3. 0.75
• 4. 1

Question: Class AB operation is often used in power large signal amplifiers in order to_________?

• 1. get maximum efficiency
• 2. remove even harmonics
• 3. overcome a crossover distortion
• 4. reducing collector dissipation

Question: Negative feedback in an amplifier____________?

• 1. Reduces gain
• 2. Increase frequency &phase distortion
• 3. Reduces bandwidth
• 4. Increases noise

Question: The current gain of a bipolar transistor drops at high frequencies because of____________?

• 1. Transistor capacitances
• 2. High current effects in the base
• 3. Parasitic inductive elements
• 4. The early effect

Question: Generally, the gain of a transistor amplifier falls at high frequencies due to the___________?

• 1. Internal Capacitance of the device
• 2. Coupling capacitor at the input
• 3. Skin effect
• 4. Coupling capacitor at the output

Question: The action of JFET in its equivalent circuit can best be represented as a_____________?

• 1. Current controlled Current source
• 2. Current controlled voltage source
• 3. Voltage controlled voltage source
• 4. voltage controlled current source

Question: In a full-wave rectifier using two ideal diodes,Vdc & Vm are the dc & peak values of the voltage respectively across a resistive load. If PIV is the peak inverse voltage of the diode, then the appropriate relationships for this rectifier is____________?

• 1. Vdc = Vm/π, PIV=2Vm
• 2. Vdc = 2Vm/π, PIV=2vm
• 3. Vdc = 2Vm/π, PIV=Vm
• 4. Vdc = Vm/π, PIV=Vm

Question: The most commonly used amplifier in sample & hold circuits is______________?

• 1. A unity gain non-inverting amplifier
• 2. A unity gain inverting amplifier
• 3. An inverting amplifier with a gain of 10
• 4. An inverting amplifiers with a gain of 100

Question: Introducing a resistor in the emitter of a common amplifier stabilizes the dc operating point against variations in____________?

• 1. Only the temperature
• 2. only the β of the transistor
• 3. Both Temperature & β
• 4. None of the above