A closely wound rectangular coil of 80 turns has dimensions of 25.0 cm by 40.0 cm. The plane of the coil is rotated from a position where it makes an angle of 37.0° with a magnetic field of 1.70 T to a position perpendicular to the field. The rotation takes 0.0600 s. What is the average emf induced in the coil?
> Distinguish between term life insurance and cash-value life insurance.
> What are your thoughts on this comment? “Younger workers today face some serious challenges in deciding where to invest their retirement funds.”
> Distinguish between the government health program called Medicare and Medicaid.
> What is a high-deductible health insurance plan and how does it work with a health savings account (HSA).
> Distinguish between a traditional health insurance plan and a health maintenance organizations (HMO).
> Summarize how an employer’s group health care plan provides coverage to employees.
> Explain how managed care has reduced the cost of health care in America.
> Differentiate between independent agents and exclusive agents.
> Summarize how companies select among insurance applicants.
> Summarize how to use deductibles, coinsurance, hazard reduction, and loss reduction to lower the cost of insurance.
> Why is the principle of indemnity so important to insurance sellers?
> Distinguish among the three types of hazards.
> Do you know anyone who has estimated his or her retirement savings goal in today’s dollars? Offer two reasons why many people do not perform those calculations. Offer two reasons why it would be smart for people to determine a financial target
> Maria Hernandez was reviewing her recent bank credit card account statement when she found two charges that she and Victor could not have made. The charges were for rental of a hotel room and purchase of a meal on the same day in a distant city. These ch
> A parallel-plate, air-filled capacitor is being charged as in Fig. 29.23. The circular plates have radius 4.00 cm, and at a particular instant the conduction current in the wires is 0.520 A. Fig. 29.23: (a). What is the displacement current density j
> A metal ring 4.50 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. These magnets produce an initial uniform field of 1.12 T between them but are gradually pulled a
> A long, straight solenoid with a cross-sectional area of 8.00 cm2 is wound with 90 turns of wire per centimeter, and the windings carry a current of 0.350 A. A second winding of 12 turns encircles the solenoid at its center. The current in the solenoid i
> The magnetic field
> A long, thin solenoid has 900 turns per meter and radius 2.50 cm. The current in the solenoid is increasing at a uniform rate of 36.0 A/s. What is the magnitude of the induced electric field at a point near the center of the solenoid and (a). 0.500 cm fr
> The magnetic field within a long, straight solenoid with a circular cross section and radius R is increasing at a rate of dB/dt. (a). What is the rate of change of flux through a circle with radius r1 inside the solenoid, normal to the axis of the solen
> Hall-effect voltages are much greater for relatively poor conductors (such as germanium) than for good conductors (such as copper), for comparable currents, fields, and dimensions. Why?
> Two 120-V light bulbs, one 25-W and one 200-W, were connected in series across a 240-V line. It seemed like a good idea at the time, but one bulb burned out almost immediately. Which one burned out, and why?
> A straight, vertical wire carries a current of 2.60 A downward in a region between the poles of a large superconducting electromagnet, where the magnetic field has magnitude B = 0.588 T and is horizontal. What are the magnitude and direction of the magne
> A rectangular loop of wire with dimensions 1.50 cm by 8.00 cm and resistance R = 0.600 Ω is being pulled to the right out of a region of uniform magnetic field. The magnetic field has magnitude B = 2.40 T and is directed into the plan
> A rectangular circuit is moved at a constant velocity of 3.0 m/s into, through, and then out of a uniform 1.25-T magnetic field, as shown in Fig. E29.35. The magnetic-field region is considerably wider than 50.0 cm. Find the magnitude and direction (cloc
> Blood contains positive and negative ions and thus is a conductor. A blood vessel, therefore, can be viewed as an electrical wire. We can even picture the flowing blood as a series of parallel conducting slabs whose thickness is the diameter d of the ves
> A 0.250-m-long bar moves on parallel rails that are connected through a 6.00-Ω resistor, as shown in Fig. E29.33, so the apparatus makes a complete circuit. You can ignore the resistance of the bar and rails. The circuit is in a unifo
> Consider the circuit shown in Fig. E29.31, but with the bar moving to the right with speed v. As in Exercise 29.31, the bar has length 0.360 m, R = 45.0 Ω, and B = 0.650 T. Exercise 29.31: A 0.360-m-long metal bar is pulled to the
> A 0.360-m-long metal bar is pulled to the left by an applied force F. The bar rides on parallel metal rails connected through a 45.0- Ω resistor, as shown in Fig. E29.31, so the apparatus makes a complete circuit. You can ignore the r
> A 0.650-m-long metal bar is pulled to the right at a steady 5.0 m/s perpendicular to a uniform, 0.750-T magnetic field. The bar rides on parallel metal rails connected through a 25.0-Ω resistor (Fig. E29.30), so the apparatus makes a
> The conducting rod ab shown in Fig. E29.29 makes contact with metal rails ca and db. The apparatus is in a uniform magnetic field of 0.800 T, perpendicular to the plane of the figure. Fig. E29.29: (a). Find the magnitude of the emf induced in the rod
> A rectangle measuring 30.0 cm by 40.0 cm is located inside a region of a spatially uniform magnetic field of 1.25 T, with the field perpendicular to the plane of the coil (Fig. E29.26). The coil is pulled out at a steady rate of 2.00 cm/s traveling perpe
> The magnetic force acting on a charged particle can never do work because at every instant the force is perpendicular to the velocity. The torque exerted by a magnetic field can do work on a current loop when the loop rotates. Explain how these seemingly
> A thin, 50.0-cm-long metal bar with mass 750 g rests on, but is not attached to, two metallic supports in a uniform 0.450-T magnetic field, as shown in Fig. E27.37. A battery and a 25.0-Ω resistor in series are connected to the supports. Fi
> Two closed loops A and C are close to a long wire carrying a current I (Fig. E29.17). Fig. E29.17: (a). Find the direction (clockwise or counterclockwise) of the current induced in each loop if I is steadily decreasing. (b). While I is decreasing, wh
> The current I in a long, straight wire is constant and is directed toward the right as in Fig. E29.16. Conducting loops, A, B, C, and D are moving, in the directions shown, near the wire. Fig. E29.16: (a). For each loop, is the direction of the induc
> A circular loop of wire is in a region of spatially uniform magnetic field, as shown in Fig. E29.15. The magnetic field is directed into the plane of the figure. Determine the direction (clockwise or counterclockwise) of the induced current in the loop w
> A circular loop of wire with radius r = 0.0250 m and resistance R = 0.390 Ω is in a region of spatially uniform magnetic field, as shown in Fig. E29.23. The magnetic field is directed into the plane of the figure. At t = 0, B = 0. The
> A circular loop of wire with radius r = 0.0480 m and resistance R = 0.160 Ω is in a region of spatially uniform magnetic field, as shown in Fig. E29.22. The magnetic field is directed out of the plane of the figure. The magnetic field
> A small, circular ring is inside a larger loop that is connected to a battery and a switch (Fig. E29.21). Use Lenz’s law to find the direction of the current induced in the small ring Fig. E29.21: / / (a). just after switch S is closed; (b). after S
> A cardboard tube is wrapped with two windings of insulated wire wound in opposite directions, as shown in Fig. E29.20. Terminals a and b of winding A may be connected to a battery through a reversing switch. State whether the induced current in the resis
> Using Lenz’s law, determine the direction of the current in resistor ab of Fig. E29.19 when Fig. E29.19: (a). switch S is opened after having been closed for several minutes; (b). coil B is brought closer to coil A with the switch
> The current in Fig. E29.18 obeys the equation I(t) = I0 e-bt, where b > 0. Find the direction (clockwise or counterclockwise) of the current induced in the round coil for t > 0. Fig. E29.18:
> A closely wound search coil (see Exercise 29.3) has an area of 3.20 cm2, 120 turns, and a resistance of 60.0 Ω. It is connected to a charge-measuring instrument whose resistance is 45.0 Ω. When the coil is rotated quickly from a position parallel to a un
> An electromagnet produces a magnetic field of 0.550 T in a cylindrical region of radius 2.50 cm between its poles. A straight wire carrying a current of 10.8 A passes through the center of this region and is perpendicular to both the axis of the cylindri
> Will the capacitors in the circuits shown in Fig. Q26.18 charge at the same rate when the switch S is closed? If not, in which circuit will the capacitors charge more rapidly? Explain. Fig. Q26.18: (a) R S. (b)
> One practical way to measure magnetic field strength uses a small, closely wound coil called a search coil. The coil is initially held with its plane perpendicular to a magnetic field. The coil is then either quickly rotated a quarter-turn about a diamet
> A flat, rectangular coil of dimensions l and w is pulled with uniform speed v through a uniform magnetic field B with the plane of its area perpendicular to the field (Fig. E29.14). Fig. E29.14: (a). Find the emf induced in this coil. (b). If the sp
> In a region of space, a magnetic field points in the +x-direction (toward the right). Its magnitude varies with position according to the formula Bx = B0 + bx, where B0 and b are positive constants, for x > 0. A flat coil of area A moves with uniform spe
> A circular loop of flexible iron wire has an initial circumference of 165.0 cm, but its circumference is decreasing at a constant rate of 12.0 cm/s due to a tangential pull on the wire. The loop is in a constant, uniform magnetic field oriented perpendic
> A flat, circular, steel loop of radius 75 cm is at rest in a uniform magnetic field, as shown in an edge-on view in Fig. E29.8. The field is changing with time, according to B(t) = (1.4 T) e-(0.057 s-1)t. Fig. E29.8: (a). Find the emf induced in the
> A long solenoid with 60 turns of wire per centimeter carries a current of 0.15 A. The wire that makes up the solenoid is wrapped around a solid core of silicon steel (Km = 5200). (The wire of the solenoid is jacketed with an insulator so that none of the
> A solid conductor with radius a is supported by insulating disks on the axis of a conducting tube with inner radius b and outer radius c (Fig. E28.43). The central conductor and tube carry equal currents I in opposite directions. The currents are distrib
> An ideal toroidal solenoid (see Example 28.10) has inner radius r1 = 15.0 cm and outer radius r2 = 18.0 cm. The solenoid has 250 turns and carries a current of 8.50 A. What is the magnitude of the magnetic field at the following distances from the center
> A long wire carrying 4.50 A of current makes two 90 bends, as shown in Fig. E27.35. The bent part of the wire passes through a uniform 0.240-T magnetic field directed as shown in the figure and confined to a limited region of space. Find the magnitude an
> A toroidal solenoid has an inner radius of 12.0 cm and an outer radius of 15.0 cm. It carries a current of 1.50 A. How many equally spaced turns must it have so that it will produce a magnetic field of 3.75 mT at points within the coils 14.0 cm from its
> Each of the lettered points at the corners of the cube in Fig. Q27.12 represents a positive charge q moving with a velocity of magnitude v in the direction indicated. The region in the figure is in a uniform magnetic field B , parallel to the x-axis and
> A solenoid is designed to produce a magnetic field of 0.0270 T at its center. It has radius 1.40 cm and length 40.0 cm, and the wire can carry a maximum current of 12.0 A. (a). What minimum number of turns per unit length must the solenoid have? (b). Wh
> Repeat Exercise 28.43 for the case in which the current in the central, solid conductor is I1, the current in the tube is I2, and these currents are in the same direction rather than in opposite directions. Exercise 28.43: A solid conductor with radius
> Figure E28.40 shows, in cross section, several conductors that carry currents through the plane of the figure. The currents have the magnitudes I1 = 4.0 A, I2 = 6.0 A, and I3 = 2.0 A, and the directions shown. Four paths, labeled a through d, are shown.
> A closed curve encircles several conductors. The line integral
> Calculate the magnitude of the magnetic field at point P of Fig. E28.35 in terms of R, I1, and I2. What does your expression give when I1 = I2? Fig. E28.35: R P R
> The magnetic field around the head has been measured to be approximately 3.0 × 10-8 G. Although the currents that cause this field are quite complicated, we can get a rough estimate of their size by modeling them as a single circular current loop 16 cm (
> In a 1.25-T magnetic field directed vertically upward, a particle having a charge of magnitude 8.50 µC and initially moving northward at 4.75 km/s is deflected toward the east. (a). What is the sign of the charge of this particle? Make a sketch to illus
> A particle of mass 0.195 g carries a charge of -2.50 × 10-8 C. The particle is given an initial horizontal velocity that is due north and has magnitude 4.00 × 104 m/s. What are the magnitude and direction of the minimum magnetic field that will keep the
> A group of particles is traveling in a magnetic field of unknown magnitude and direction. You observe that a proton moving at 1.50 km/s in the +x-direction experiences a force of 2.25 × 10-16 N in the +y-direction, and an electron moving at 4.75 km/s in
> A particle with charge -5.60 nC is moving in a uniform magnetic field
> Two concentric circular loops of wire lie on a tabletop, one inside the other. The inner wire has a diameter of 20.0 cm and carries a clockwise current of 12.0 A, as viewed from above, and the outer wire has a diameter of 30.0 cm. What must be the magnit
> An electron moves at 1.40 × 106 m/s through a region in which there is a magnetic field of unspecified direction and magnitude 7.40 × 10-2 T. (a). What are the largest and smallest possible magnitudes of the acceleration of the electron due to the magne
> A 1500-W electric heater is plugged into the outlet of a 120-V circuit that has a 20-A circuit breaker. You plug an electric hair dryer into the same outlet. The hair dryer has power settings of 600 W, 900 W, 1200 W, and 1500 W. You start with the hair d
> The heating element of an electric dryer is rated at 4.1 kW when connected to a 240-V line. (a). What is the current in the heating element? Is 12-gauge wire large enough to supply this current? (b). What is the resistance of the dryer’s heating element
> You connect a battery, resistor, and capacitor as in Fig. 26.20a, where R = 12.0Ω and C = 5.00 × 10-6 F. The switch S is closed at t = 0. When the current in the circuit has magnitude 3.00 A, the charge on the capacitor i
> A 4.60-µF capacitor that is initially uncharged is connected in series with a 7.50-k Ω resistor and an emf source with
> You connect a battery, resistor, and capacitor as in Fig. 26.20a, where
> How could the direction of a magnetic field be determined by making only qualitative observations of the magnetic force on a straight wire carrying a current?
> A capacitor is charged to a potential of 12.0 V and is then connected to a voltmeter having an internal resistance of 3.40 M Ω. After a time of 4.00 s the voltmeter reads 3.0 V. What are (a). the capacitance and (b). the time constant of the circuit?
> In the circuit shown in Fig. E26.51, C = 5.90 µF,
> A 12.0-µF capacitor is charged to a potential of 50.0 V and then discharged through a 225-Ω resistor. How long does it take the capacitor to lose (a). half of its charge and (b). half of its stored energy?
> A single circular current loop 10.0 cm in diameter carries a 2.00-A current. (a). What is the magnetic field at the center of this loop? (b). Suppose that we now connect 1000 of these loops in series within a 500-cm length to make a solenoid 500 cm lon
> A particle with initial velocity
> In the circuit in Fig. E26.49 the capacitors are initially uncharged, the battery has no internal resistance, and the ammeter is idealized. Find the ammeter reading Fig. E26.49: (a). just after the switch S is closed and (b). after S has been closed
> A 1.50-µF capacitor is charging through a 12.0-Ω resistor using a 10.0-V battery. What will be the current when the capacitor has acquired 1 4 of its maximum charge? Will it be 1 4 of the maximum current?
> In the circuit shown in Fig. E26.47 each capacitor initially has a charge of magnitude 3.50 nC on its plates. After the switch S is closed, what will be the current in the circuit at the instant that the capacitors have lost 80.0% of their initial stored
> A resistor and a capacitor are connected in series to an emf source. The time constant for the circuit is 0.780 s. (a). A second capacitor, identical to the first, is added in series. What is the time constant for this new circuit? (b). In the original
> An emf source with
> A 12.4-µF capacitor is connected through a 0.895-M resistor to a constant potential difference of 60.0 V. (a). Compute the charge on the capacitor at the following times after the connections are made: 0, 5.0 s, 10.0 s, 20.0 s, and 100.0 s. (b). Comput
> In the circuit shown in Fig. E26.43 both capacitors are initially charged to 45.0 V. Fig. E26.43: (a). How long after closing the switch S will the potential across each capacitor be reduced to 10.0 V, and (b). what will be the current at that time?
> A resistor consists of three identical metal strips connected as shown in Fig. Q26.8. If one of the strips is cut out, does the ammeter reading increase, decrease, or stay the same? Why? Fig. Q26.8: A
> The resistance of a galvanometer coil is 25.0 Ω, and the current required for full-scale deflection is 500 µA. (a). Show in a diagram how to convert the galvanometer to an ammeter reading 20.0 mA full scale, and compute the shunt resistance. (b). Show
> A galvanometer having a resistance of 25.0 Ω has a 1.00-Ω shunt resistance installed to convert it to an ammeter. It is then used to measure the current in a circuit consisting of a 15.0- Ω resistor connected across the terminals of a 25.0-V battery
> A closely wound, circular coil with radius 2.40 cm has 800 turns. (a). What must the current in the coil be if the magnetic field at the center of the coil is 0.0770 T? (b). At what distance x from the center of the coil, on the axis of the coil, is th
> A circuit consists of a series combination of 6.00-kΩ and 5.00-kΩ resistors connected across a 50.0-V battery having negligible internal resistance. You want to measure the true potential difference (that is, the potential difference without the meter
> The resistance of the coil of a pivotedcoil galvanometer is 9.36 , and a current of 0.0224 A causes it to deflect full scale. We want to convert this galvanometer to an ammeter reading 20.0 A full scale. The only shunt available has a resistance of 0.025
> In the circuit shown in Fig. E26.25 find Fig. E26.25: (a). the current in resistor R; (b). the resistance R; (c). the unknown emf E. (d). If the circuit is broken at point x, what is the current in resistor R? 28.0 V R + 4.00 A ww X 6.00 N 6.0
> The batteries shown in the circuit in Fig. E26.24 have negligibly small internal resistances. Find the current through Fig. E26.24: (a). the 30.0-Ω resistor; (b). the 20.0-Ω resistor; (c). the 10.0-V battery. 30.0 20.0 N
> In the circuit shown in Fig. E26.23, ammeter A1 reads 10.0 A and the batteries have no appreciable internal resistance. Fig. E26.23: (a). What is the resistance of R? (b). Find the readings in the other ammeters. (A2) 40.0 N R (A) (A4 (A3 20.0 N
> In the circuit shown in Fig. E26.34, the 6.0-Ω resistor is consuming energy at a rate of 24 J/s when the current through it flows as shown. Fig. E26.34: (a). Find the current through the ammeter A. (b). What are the polarity and emf E of
> In the circuit shown in Fig. E26.33 all meters are idealized and the batteries have no appreciable internal resistance. Fig. E26.33: (a). Find the reading of the voltmeter with the switch S open. Which point is at a higher potential: a or b? (b). Wi
> In the circuit shown in Fig. E26.32 both batteries have insignificant internal resistance and the idealized ammeter reads 1.50 A in the direction shown. Find the emf
> A battery with no internal resistance is connected across identical light bulbs as shown in Fig. Q26.7. When you close the switch S, will the brightness of bulbs B1 and B2 change? If so, how will it change? Explain. Fig. Q26.7: B B1 B2
