ECE :: Exam Questions Paper
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A junction FET, can be used as a voltage variable resistor
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A fully charged mobile phone with a 12 V battery is good for a 20 minute talktime. Assume that, during the talk time, the battery delivers a constant current of 2 A and its voltage drops linearly from 12 V to 10 V as shown in the figure. How much energy does the battery deliver during this talk time?
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In a material, the Fermi level is located between the centre of the forbidden band and the conduction band. Then what is that material?
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Consider an SSB signal when the modulating signal is x(t). Let x(t) represents the complex conjugate of x(t) and is its Hilbert transform. The envelope of SSB signal is:
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An audio signal is to be transmitted digitally. Which is the system best suited for good fidelity?
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The pre-emphasis in FM aids in providing extra noise immunity by
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Two products are sold from a vending machine, which has two push buttons P1 and P2. When a button is pressed, the price of the corresponding product is displayed in a 7-segment display. If no buttons are pressed, '0' is displayed, signifying 'Rs' .0'. If only P1 is pressed, '2' is displayed, signifying 'Rs. 2'.
If only P2 is pressed, '5' is displayed, signifying 'Rs. 5'.
If both P1 and P2 are pressed, 'E' is displayed, signifying 'Error'. The names of the segments in the 7-segment display, and the glow of the display for '0', '2', '5' and 'E', are shown below.
Consider- push button pressed/not pressed is equivalent to logic 1/ 0 respectively
- a segment a to g are considered as functions of P1 and P2, then which of the respectively.
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A negative-feedback closed-loop system is supplied to an input 5 V. The system has a forward gain of 1 and a feedback gain of 1 and a feedback gain of 1. What is the output voltage?