St Columba’s High School Electricity and Electronics

St Columba’s High SchoolElectricity and Electronics Op-amps

27 An op amp is : • A frequency amplifier • A current amplifier • A voltage amplifier • A power amplifier

8 In the ideal op amp shown what is a) the potential at and b)the current flowing into the inverting pin ? • 0.5 V and 0 mA • 0 V and 0.05 mA • 0.5 V and 0.05 mA • 0 V and 0 mA

79 Calculate Vout • 5.0 V • - 0.05 V • -5.0 V • 0.05 V

90 What is the value of Vout if Vin = 2.0 V ? • -20 V • + 0.2 V • -13.5 V • +13.5 V

28 The input voltage has a frequency of 280 Hz and a peak value of 0.5 V. The frequency of the output voltage is : • 14 Hz • 28 Hz • 280 Hz • 560 Hz

89 If the variable resistor is altered over the range 0 to 200 kΩ what is the range of the gain ? • 0 to 1 • 0 to 10 • 1 to 10 • 1 to 11

29 What is the gain expression for the differential mode ? • ( V1 – V2 )x 10 • ( V2- V1 )x - 10 • ( V2 – V1 )x 10 • ( V1 – V2 )x -10

26 The 5 V bulb does not light properly because : • Vout is negative • Iout is zero amps • Vout is positive • Iout is in the micro amp range

90 Calculate R1 if Vout = 2.5 V • 50 kΩ • 20 kΩ • 5 kΩ • 2 kΩ

90 Calculate the unknown resistance if the amp is operating in the differential mode : • 0.4 kΩ • 10 kΩ • 5 kΩ • 50 kΩ

90 Calculate the value of V2 – V1 if Vout = 10 V • 2 V • - 2V • 1.25 V • - 1.25 V

500 mV V1 90 mV 90 Calculate V1. Vout = 500 mV and V2 =90 mV • 130 mV • -40 mV • -130 mV • 40 mV

St Columba’s High School Electricity and Electronics