Electronic Circuits Fundamentals and Applications 4th. Edition by Mike Tooley | 9781138828926 | 1138828920

Electronic Devices and Circuits

Electronic Circuits Fundamentals and Applications

168 SOLVED PROBLEMS

1 SOLVED PROBLEMS

Question: 5.57

A 150 μF capacitor is charged to a potential of 150 V. The capacitor is then removed from the charging source and connected to a 2 MΩ resistor. Determine the capacitor voltage 1 minute later. ...

Verified Answer:

We will solve this problem using the tabular metho...

Question: 19.3

A transistor has an absolute maximum junction temperature rating of 150° and a thermal resistance from junction to case of 1.0°C/W. If the device is fitted with a washer and mounting kit having a thermal resistance of 1.25°C/W and a heatsink of 2.75°C/W, determine whether the maximum ratings are ...

Verified Answer:

Applying equation (6) gives:

T_{Jmax} = (2...

Question: 7.9

The characteristic curves shown in Fig. 7.37 relate to a transistor operating in common-emitter mode. If the transistor is operated with I B = 30 μA, a load resistor of 1.2 kΩ and an 18 V supply, determine the quiescent values of collector voltage and current (VCQ and I CQ). Also determine the ...

Verified Answer:

First we need to construct the load line. The two ...

Question: A8.18

A capacitor is charged to a potential of 100 V. It is then disconnected from its charging source and left to discharge through a resistor. If it takes 10 s for the voltage to fall to 50 V, how long will it take to fall to 10 V? ...

Verified Answer:

Here we are dealing with exponential decay. If we ...

Question: A8.17

An amplifier has a power gain of 33 dB. What input power will be required to produce an output power of 11 W? ...

Verified Answer:

Now power gain expressed in decibels will be given...

Question: A8.16

An amplifier has a power gain of 27,000. Express this in Bels (B) and decibels (dB). ...

Verified Answer:

In Bels, power gain =

log_{10}

(...

Question: A8.15

Part of the control logic for an intruder alarm is shown in Fig. A8.31. Determine the logic required to select the Y4 output and verify that the Y3 output is permanently selected and unaffected by the states of S1 and S2. ...

Verified Answer:

Each logic gate shown in Fig. A8.31 is a two-input...

Question: A8.14

The voltage appearing at the secondary winding of a transformer is shown in Fig. A8.19. Determine: (a) the period of the voltage (b) the value of the voltage when (i) t = 5 ms and (ii) t = 35 ms (c) the maximum and minimum values of voltage (d) the average value of the voltage during the time ...

Verified Answer:

All of the above can be obtained from the graph of...

Question: A8.13

The voltage applied to a high voltage rectifier is given by the equation: ν = 800 sin(314 t) Determine the voltage when: (a) t = 1 ms (b) t = 15 ms. ...

Verified Answer:

We can easily solve this problem by substituting v...

Question: A8.12

The following data were obtained while making measurements on an N-channel field effect transistor: Plot a graph showing how drain current (I D) varies with gate-source voltage (VGS) and use the graph to determine: (a) the value of I D when VGS = 0 V, and (b) the slope of the graph (expressed in mA ...

Verified Answer:

The data have been shown plotted in Fig. A8.10. No...

Question: 1.13

A power of 300 mW is dissipated in a circuit when a voltage of 1,500 V is applied. Determine the current supplied to the circuit. ...

Verified Answer:

Current is equal to power divided by voltage. Thus...