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In FIGURE Q14.5, is p A larger than, smaller than, or equal to p B ? Explain. A B FIGURE Q14.5 Rank in order, from largest to smallest, the densities of blocks a, b, and c in FIGURE Q14.6. Explain. FIGURE Q14.6 In the switched-capacitor amplifier of Fig. 6.9a, assume that the source of M 4 is connected to V S instead of to ground. Calculate the output volt-age that appears during Ï 2 for a given V S .... (a) Calculate and sketch the output voltage waveform of the switched-capacitor integrator of Fig. 6.10a from t =0 to t =20 μs assuming a fixed Vs = 1 V and a clock rate of 1 MHz. Assume... Draw a two-stage op amp similar to the op amp in Fig. 6.16 except reverse the polarity of every transistor. For example, the resulting op amp should have an n.-channel input pair. Calculate the... (a) Equation 6.69 gives the random input off-set voltage of the op amp in Fig. 6.16. Explain the polarity of each term in (6.69) by assuming that the matching is perfect except for the term under... The deepest point in the ocean is 11 km below sea level, deeper than Mt. Everest is tall. What is the pressure in atmospheres at this depth? A 3.0-cm-diameter tube is held upright and filled to the top with mercury. The mercury pressure at the bottom of the tube the pressure in excess of atmospheric pressureis 50 kPa. How tall is the tube? a. What volume of water has the same mass as 8.0 m 3 of ethyl alcohol? b. If this volume of water is in a cubic tank, what is the pressure at the bottom? The two identical beakers in FIGURE Q14.9 are filled to the same height with water. Beaker B has a plastic sphere floating in it. Which beaker, with all its contents, weighs more? Or are they equal?... Calculate the common-mode input range of the op amp in Fig. 6.25. Assume that all the transistors are enhancement-mode devices with |V t | = 1V,and ignore the body effect. Also assume that the... Draw a telescopic-cascode op amp similar to the first stage in Fig. 6.25 except use an n-channel input pair and a high-swing p-type cascode current-mirror load. Calculate the maximum output swing in... Wind blows over the house in FIGURE Q14.11. A window on the ground floor is open. Is there an airflow through the house? If so, does the air flow in the window and out the chimney, or in the chimney... Draw the schematic of a folded-cascode op amp similar to the op amp in Fig. 6.28 except with two layers of both n- and p-type cascodes. Choose a current mirror that maximizes the output swing. Assume... A 20-cm-diameter circular cover is placed over a 10-cm diameter hole that leads into an evacuated chamber. The pressure in the chamber is 20 kPa. How much force is required to pull the cover off? A wire is stretched right to the breaking point by a 5000 N force. A longer wire made of the same material has the same diameter. Is the force that will stretch it right to the breaking point larger... What is the height of a water barometer at atmospheric pressure? What is the minimum hose diameter of an ideal vacuum cleaner that could lift a 10 kg (22 lb) dog off the floor? A 6.00-cm-diameter sphere with a mass of 89.3 g is neutrally buoyant in a liquid. Identify the liquid. Astronauts visiting a new planet find a lake filled with an unknown liquid. They have with them a plastic cube, 6.0 cm on each side, with a density of 840 kg/m 3 . First they weigh the cube with a... In Fig. 6.31b, resistive loads were used to extend the common-mode input range to include V EE . Fig. 6.62 shows another circuit with this characteristic. Find the common-mode range of this circuit.... A sphere completely submerged in water is tethered to the bottom with a string. The tension in the string is one-third the weight of the sphere. What is the density of the sphere? There is a disk of cartilage between each pair of vertebrae in your spine. Youngs modulus for cartilage is 1.0 10 6 N/m 2 . Suppose a relaxed disk is 4.0 cm in diameter and 5.0 mm thick. If a disk... (a) Suppose that the npn and pnp transistors in the input stage of the NE5234 op amp are changed into n-channel and p-channel MOS transistors, respectively. If transistors conducting nonzero current... (a) Use the Miller approximation to calculate the 3-dB frequency of the small-signal voltage gain of a common-emitter transistor stage as shown in Fig. 7.2a using R S = 5 kΩ, R L = 3... a. In FIGURE P14.38, how much force does the fluid exert on the end of the cylinder at A? b. How much force does the fluid exert on the end of the cylinder at B? - 10 kg floating piston 4.0 cm 100 cm... A long horizontal tube has a square cross section with sides of width L. A fluid moves through the tube with speed v 0 . The tube then changes to a circular cross section with diameter L. What is the... Repeat Problem 7.3 for the MOS circuit in Problem 7.2. Data from Prob. 7.3: Calculate an expression for the output impedance of the circuit in Problem 7.1 as seen by RL and form an equivalent... A common-base stage has the following parameters: I C = 0.5 mA, C = 10 pF, C = 0.3 pF, r b = 200 , = 100, r o = , R L = 0, and RS = . (a) Calculate an expression for the small-signal current gain... How many correct experiments do we need to disprove a theory? How many do we need to prove a theory? Explain. Suppose you are asked to compute the tangent of 5.00 meters. Is this possible? Why or why not? An amplifier stage is shown in Fig. 7.41 where bias current I B is adjusted so that V O = 0 V dc. Take V SUPPLY = 10 V. (a) Calculate the low-frequency, small-signal trans-resistance Ï o /i i... A differential circuit employing active loads is shown in Fig. 7.42. Bias voltage V B is adjusted so that the collectors of Q 1 and Q 2 are at +5 V dc. Biasing resistors are R B1 = 10 kΩ... A two-stage amplifier is shown in Fig. 7.46. Calculate the low-frequency, small-signal gain and use the zero-value time-constant method to estimate the 3-dB frequency. Calculate the 10 to 90 percent... (a) A wideband MOS amplifier stage is shown in Fig. 7.48. Calculate the small-signal, low-frequency gain and use the zero-value timeconstant method to estimate the 3-dB bandwidth. Use μ... Let A(Vector) represent any nonzero vector. Why is A(Vector)/A a unit vector, and what is its direction? If is the angle that A(Vector) makes with the +x-axis, explain why (A(Vector) /A) i is... For the BiCMOS circuit of Fig. 3.78, use the zero-value time-constant method to estimate the first and second most dominant poles of the circuit. Assume an input voltage drive. Use bipolar transistor... A rocket starts from rest and moves upward from the surface of the earth. For the first 10.0 s of its motion, the vertical acceleration of the rocket is given by a y = (2.80 m/s 3 )t, where the... Calculate the pole and zero associated with the current-mirror load in Fig. 7.33 if I D3 = 100 µA, |V ov3 | = 0.2 V, and C x = 0.1 pF. Fig. 7.33: VDD M4 V. in- M2, in+ M1 ITAIL -Vss (a) g14 3... For the characteristic of Fig. 8.2 the following data apply: S o2 = 15 V S o1 = 7V a 1 = 50,000 a 2 = 20,000 (a) Calculate and sketch the overall transfer characteristic of Fig 8.3 for the above... For the shunt-shunt feedback amplifier of Fig. 8.15a, take R F =100 k and R L = 15 k. For the op amp, assume that R i =500 k, R o = 200, and a v = 75,000. Calculate input resistance, output... Two cars collide at an intersection. Car A, with a mass of 2000 kg, is going from west to east, while car B, of mass 1500 kg, is going from north to south at 15 m/s. As a result, the two cars become... A feedback amplifier is shown in Fig. 8.49. Device data are as follows: β npn = 200, β pnp = 100, |V BE(on) | = 0.7V, r b = 0, and |V A | = . If the dc input voltage is zero,... An op amp with low-frequency gain of 108 dB has three negative real poles with magnitudes 30 kHz, 500 kHz, and 10 MHz before compensation. The circuit is compensated by placing a capacitance across... An egg is released from rest from the roof of a building and falls to the ground. As the egg falls, what happens to the momentum of the system of the egg plus the earth? For the feedback circuit in Fig. 12.46, the capacitor values are C 1 = C 2 = 4 pF and C L = 6 pF. The op amp is the folded-cascode amplifier in Fig. 12.40 with low-frequency gain adm0 = 1280 and g m1... A force of 520 N keeps a certain spring stretched a distance of 0.200 m. (a) What is the potential energy of the spring when it is stretched 0.200 m? (b) What is its potential energy when it is... A 25.0-kg child plays on a swing having support ropes that are 2.20 m long. Her brother pulls her back until the ropes are 42.0 from the vertical and releases her from rest. (a) What is her potential... A projectile has the same initial kinetic energy no matter what the angle of projection. Why doesnt it rise to the same maximum height in each case? If work W is required to stretch a spring a distance x from its unstretched length, what work (in terms of W) is required to stretch the spring an additional distance x? A nonzero net force acts on an object. Is it possible for any of the following quantities to be constant: the objects (a) Speed; (b) Velocity; (c) Kinetic energy? Calculate equivalent input noise voltage and current generators for the circuit of Fig. 11.49 (omitting R S ). Using these results, calculate the total equivalent input noise current in a 2-MHz... A falling brick has a mass of 1.5 kg and is moving straight downward with a speed of 5.0 m/s. A 1.5-kg physics book is sliding across the floor with a speed of 5.0 m/s. A 1.5-kg melon is traveling... Calculate the return ratio for the feedback circuit in Fig. 9.62. Assume that the amplifier voltage gain is constant with a v > 0. Show that this feedback circuit is always stable if each impedance... The feedback circuit in Fig. 9.55 is a switched-capacitor circuit during one clock phase. Assume the op amp is the telescopic-cascode op amp in Fig. 9.54. Take C L = 1.5 pF, C I = 4 pF, C S = 0.4 pF,... For the three-stage op amp with nested Miller compensation in Fig. 9.30c, determine the values of the compensation capacitors that give a 60¦ phase margin when the op amp is in a unity-gain... To keep the forces on the riders within allowable limits, many loop-the-loop roller coaster rides are designed so that the loop is not a perfect circle but instead has a larger radius of curvature at... The centrifugal force is not included in the free-body diagrams of Figs. 5.34b and 5.35. Explain why not. n cos B n sin B Grud w-mg In designing structures in an earthquake-prone region, how should the natural frequencies of oscillation of a structure relate to typical earthquake frequencies? Why? Should the structure have a... For a simple pendulum, clearly distinguish between (the angular speed) and (the angular frequency). Which is constant and which is variable? Could a standard of time be based on the period of a certain standard pendulum? What advantages and disadvantages would such a standard have compared to the actual present-day standard discussed in... A CMOS feedback amplifier is shown in Fig. 8.53. If the dc input voltage is zero, calculate the overall gain o / i and the output resistance. Compare your answer with a SPICE simulation. Use n C ox... The ac schematics of a common-source stage and a common-sourcecommon-gate (cascode) stage are shown in Fig. 7.43 with R S = 10 kΩ and R L = 20 kΩ. Using the transistor and... A sinusoidal wave can be described by a cosine function, which is negative just as often as positive. So why isnt the average power delivered by this wave zero? The four strings on a violin have different thicknesses, but are all under approximately the same tension. Do waves travel faster on the thick strings or the thin strings? Why? How does the... Your uncle is in the below-deck galley of his boat while you are spear fishing in the water nearby. An errant spear makes a small hole in the boats hull, and water starts to leak into the galley. (a)... A tornado consists of a rapidly whirling air vortex. Why is the pressure always much lower in the center than at the outside? How does this condition account for the destructive power of a tornado? A channel has the following transition matrix: (a) Sketch the channel diagram showing all transition probabilities. (b) Determine the channel output probabilities assuming that the input... The input to a quantizer is a random signal having an amplitude probability density function The signal is to be quantized using four quantizing levels x i as shown in Figure 12.44. Determine the... Repeat the preceding problem assuming that the input to the quantizer has the Rayleigh probability density function Data From Problem 12.11 The input to a quantizer is a random signal having an... Derive an expression for P E for binary coherent FSK if the frequency separation of the two transmitted signals is chosen to give a minimum correlation coefficient between the two signals. That is,... Assume that the probabilities of sending the signals s 1 (t) and s 2 (t) are not equal, but are given by p and q = 1 - p, respectively. Derive an expression for P E that replaces (9.32) that takes... Write a computer simulation program to evaluate the bit error rate performance of a MMSE equalizer using LMS tap weight adjustment, thus verifying the results of Figure 9.33. 100 Unequalized; 400,000... When rubber mounting blocks are used to absorb machine vibrations through elastic hysteresis, as mentioned in Section 11.5, what becomes of the energy associated with the vibrations? There is a small but appreciable amount of elastic hysteresis in the large tendon at the back of a horses leg. Explain how this can cause damage to the tendon if a horse runs too hard for too long a... The material in human bones and elephant bones is essentially the same, but an elephant has much thicker legs. Explain why, in terms of breaking stress. In analyzing the performance of an FM discriminator, operating in the presence of noise, the post detection SNR, (SNR) D , is often determined using the approximation that the effect of modulation on... Compare the mechanical properties of a steel cable, made by twisting many thin wires together, with the properties of a solid steel rod of the same diameter. What advantages does each have? A metal wire of diameter D stretches by 0.100 mm when supporting a weight W. If the same-length wire is used to support a weight three times as heavy, what would its diameter have to be (in terms of... If a metal wire has its length doubled and its diameter tripled, by what factor does its Youngs modulus change? Why is a tapered water glass with a narrow base easier to tip over than a glass with straight sides? Does it matter whether the glass is full or empty? During pregnancy, women often develop back pains from leaning backward while walking. Why do they have to walk this way? Check the correlation between the random variables X and Y generated by the random number generator of Computer Exercise 6.2 by computing the sample correlation coefficient of 1000 pairs according to... Why is it easier to hold a 10-kg dumbbell in your hand at your side than it is to hold it with your arm extended horizontally? The mighty Zimbo claims to have leg muscles so strong that he can stand flat on his feet and lean forward to pick up an apple on the floor with his teeth. Should you pay to see him perform, or do you... In pioneer days, when a Conestoga wagon was stuck in the mud, people would grasp the wheel spokes and try to turn the wheels, rather than simply pushing the wagon. Why? Why must a water skier moving with constant velocity lean backward? What determines how far back she must lean?Draw a free-body diagram for the water skier to justify your answers. Suppose that the object in Question 11.9 is released from rest with the bar tilted at 60 above the horizontal with the ball at the upper end. As it is falling, will it (a) Rotate about its center of... You freely pivot a horseshoe from a horizontal nail through one of its nail holes. You then hang a long string with a weight at its bottom from the same nail, so that the string hangs vertically in... You can probably stand flatfooted on the floor and then rise up and balance on your tiptoes. Why are you unable do it if your toes are touching the wall of your room? Does the center of gravity of a solid body always lie within the material of the body? If not, give a counterexample. Car tires are sometimes balanced on a machine that pivots the tire and wheel about the center. Weights are placed around the wheel rim until it does not tip from the horizontal plane. Discuss this... (a) Is it possible for an object to be in translational equilibrium (the first condition) but not in rotational equilibrium (the second condition)? Illustrate your answer with a simple example. (b)... Does a rigid object in uniform rotation about a fixed axis satisfy the first and second conditions for equilibrium? Why? Does it then follow that every particle in this object is in equilibrium?... The power generated by a wind turbine is proportional to the cube of the wind velocity. Inspired by the acceleration of a fluid in a nozzle, someone proposes to install a reducer casing to capture... A helicopter has a large main rotor that rotates in a horizontal plane and provides lift. There is also a small rotor on the tail that rotates in a vertical plane. What is the purpose of the tail... A 2004 Prius with a 150-lb driver and no passengers weighs 3071 lb. The car is initially at rest. Starting at t = 0, a net horizontal force F x (t) in the +x-direction is applied to the car. The... Two objects with different masses are launched vertically into the air by placing them on identical compressed springs and then releasing the springs. The two springs are compressed by the same... Consider Section 24.3.3, where the dynamic properties of a signal transduction were analyzed. Two properties of inter est are the signal duration and the amplitude of the signal. (a) The following... When calculating the moment of inertia of an object, can we treat all its mass as if it were concentrated at the center of mass of the object? Justify your answer.
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