| 1. | A coil of 20 ohms resistance and 0.16 H inductance is connected in parallel with a 100 ?F condenser to a constant voltage variable frequency supply. The frequency (neglecting the resistance) at which the current in the main is a minimum is given by ? | |
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20 Hz
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30 Hz
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40 Hz
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50 Hz
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Report Question| 2. | The shunt element in a band pass filter ? | |
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capacitive
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inductive
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parallel combination of L and C
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series combination of L and C
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| 3. | The series element for a prototype high pass filter is ? | |
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resistive
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inductive
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capacitive
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combination of L and C
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| 4. | A capacitor with initial charge qo at t = o+ acts as ? | |
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current source
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voltage source
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short-circuit
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open-circuit
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| 5. | Which of the following values of an alternating current is indicated by a normal universal measuring instrument ? | |
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Iav
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Ir.m.s.
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Iav/2
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Imax
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| 6. | The voltage in a circuit follows the law v= 100 sin wt lf the frequency is 26 Hz, how long will it take for the voltage to rise to 50 volts ? | |
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1/50 s
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100 s
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1/300 s
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1/600 s
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| 7. | The square waveform of current has following relation between r.m..s. value and average value ? | |
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r.m.s. value is equal to average value
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r.m.s. value of current is greater than average value
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r.m.s. value of current is less than average value
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none of the above
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| 8. | An AC. voltage of 50 Hz has a maximum value of 50 V. Its value after 1/600 second after the instant the current is zero, will be ? | |
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5 V
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12.6 V
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26 V
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43.3V
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| 9. | If two sine waves of the same frequency have a phase difference of n radians, then ? | |
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both will reach their minimum values at the same instant
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both will reach their maximum values at the same instant
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when one wave reaches its maximum value, the other will reach its minimum value
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none of the above
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| 10. | A heater is rated as 230 V, 10 kW, A.C. The value 230 V refers to ? | |
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average voltage
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r.m.s. voltage
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peak voltage
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none of the above
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