Question: Four long, parallel conductors carry equal currents

> The histogram shows the distribution of the numbers of siblings (brothers and sisters) for 2000 adults surveyed in the 2012 General Social Survey. a. Describe the shape of the distribution. b. What is the typical number of siblings, approximately? c. Abo

> In 2012, the General Social Survey (GSS), a national survey conducted nearly every year, reported the number of years of formal education for 2018 people. The following histogram shows the distribution of data. a. Describe and interpret the distribution

> The histograms show triglyceride levels for 87 men and 99 women. Triglycerides are a form of fat found in blood. a. Compare the distributions of triglyceride levels for men and women. (Be sure to compare the shapes, the centers, and the spreads.) b. Trig

> The histograms show the Body Mass Index for 90 females and 89 males according to NHANES. Compare the distributions of BMIs for women and men. Be sure to compare the shapes, the centers, and the amount of variation for the two groups.

> From the histogram shown in Exercise 2.4, what is the typical number of calories for a fast food item in this sample?

> From the histogram in Exercise 2.3, approximately what is the typical pulse rate in this sample?

> The distribution of in-state annual tuition for all colleges and universities in the United States is bimodal. What is one possible reason for this bimodality?

> Babies 6 to 23 months of age with inner ear infections were given antibiotics. The children were randomly assigned to receive antibiotics for a full 10 days or to receive antibiotics for 5 days and then a placebo for 5 days. There were 229 children assig

> Researchers wanted to assess whether a theory-based, community health worker–delivered intervention for household smokers will lead to reduced secondhand smoke exposure to children in Chinese families. Smoking parents or caregivers who

> Determine the initial direction of the deflection of charged particles as they enter the magnetic fields, as shown in Figure P19.4. Figure P19.4:

> (a) Find the direction of the force on a proton (a positively charged particle) moving through the magnetic fields in Figure P19.2, as shown. (b) Repeat part (a), assuming the moving particle is an electron. Figure P19.2:

> Find the direction of the magnetic field acting on the positively charged particle moving in the various situations shown in Figure P19.3 if the direction of the magnetic force acting on it is as indicated. Figure P19.3:

> Electrons in Earth’s upper atmosphere have typical speeds near 6.00 x 105 m/s. (a) Calculate the magnitude of Earth’s magnetic field if an electron’s velocity is perpendicular to the magnetic field and its circular path has a radius of 7.00 x 10-2 m. (b)

> A mass spectrometer is used to examine the isotopes of uranium. Ions in the beam emerge from the velocity selector at a speed of 3.00 x 105 m/s and enter a uniform magnetic field of 0.600 T directed perpendicularly to the velocity of the ions. What is th

> Figure P19.14a is a diagram of a device called a velocity selector, in which particles of a specific velocity pass through undeflected while those with greater or lesser velocities are deflected either upwards or downwards. An electric field is directed

> A proton travels with a speed of 5.02 x 106 m/s at an angle of 60° with the direction of a magnetic field of magnitude 0.180 T in the positive x - direction. What are (a) The magnitude of the magnetic force on the proton and (b) The proton’s acceleration

> Sodium ions (Na+) move at 0.851 m/s through a bloodstream in the arm of a person standing near a large magnet. The magnetic field has a strength of 0.254 T and makes an angle of 51.0° with the motion of the sodium ions. The arm contains 100 cm3 of blood

> An oxygen ion (O+) moves in the xy - plane with a speed of 2.50 x 103 m/s. If a constant magnetic field is directed along the z - axis with a magnitude of 2.00 x 10-5 T, find (a) The magnitude of the magnetic force acting on the ion and (b) The magnitude

> A proton moves perpendicular to a uniform magnetic field B( at a speed of 1.00 x 107 m/s and undergoes an acceleration of 2.00 x 1013 m/s2 in the positive x - direction when its velocity is in the positive z - direction. Determine the magnitude and direc

> Two long, parallel conductors separated by 10.0 cm carry currents in the same direction. The first wire carries a current I1 = 5.00 A, and the second carries I2 = 8.00 A. (a) What is the magnitude of the magnetic field created by I1 at the location of I2

> A 1.00 - kg ball having net charge Q = 5.00 μC is thrown out of a window horizontally at a speed v = 20.0 m/s. The window is at a height h = 20.0 m above the ground. A uniform horizontal magnetic field of magnitude B = 0.0100 T is perpendicular to the pl

> A straight wire of mass 10.0 g and length 5.0 cm is suspended from two identical springs that, in turn, form a closed circuit (Fig. P19.74). The springs stretch a distance of 0.50 cm under the weight of the wire. The circuit has a total resistance of 12

> Which way would a compass point if you were at Earth’s north magnetic pole?

> Protons having a kinetic energy of 5.00 MeV are moving in the positive x - direction and enter a magnetic field of 0.0500 T in the z - direction, out of the plane of the page, and extending from x = 0 to x = 1.00 m as in Figure P19.73. (a) Calculate the

> Two long, parallel wires, each with a mass per unit length of 0.040 kg/m, are supported in a horizontal plane by 6.0 - cm - long strings, as shown in Figure P19.72. Each wire carries the same current I, causing the wires to repel each other so that the a

> Three long, parallel conductors carry currents of I = 2.0 A. Figure P19.71 is an end view of the conductors, with each current coming out of the page. Given that a = 1.0 cm, determine the magnitude and direction of the magnetic field at points A, B, and

> A uniform horizontal wire with a linear mass density of 0.50 g/m carries a 2.0 - A current. It is placed in a constant magnetic field with a strength of 4.0 x 10-3 T. The field is horizontal and perpendicular to the wire. As the wire moves upward startin

> Using an electromagnetic flow-meter (Fig. P19.69), a heart surgeon monitors the flow rate of blood through an artery. Electrodes A and B make contact with the outer surface of the blood vessel, which has interior diameter 3.00 mm. (a) For a magnetic fiel

> A 0.200 - kg metal rod carrying a current of 10.0 A glides on two horizontal rails 0.500 m apart. What vertical magnetic field is required to keep the rod moving at a constant speed if the coefficient of kinetic friction between the rod and rails is 0.10

> Two long, straight wires cross each other at right angles, as shown in Figure P19.67. (a) Find the direction and magnitude of the magnetic field at point P, which is in the same plane as the two wires. (b) Find the magnetic field at a point 30.0 cm above

> An electron moves in a circular path perpendicular to a constant magnetic field of magnitude 1.00 mT. The angular momentum of the electron about the center of the circle is 4.00 x 10-25 kg · m2/s. Determine (a) The radius of the circular path and (b) The

> Two coplanar and concentric circular loops of wire carry currents of I1 = 5.00 A and I2 = 3.00 A in opposite directions as in Figure P19.65. (a) If r1 = 12.0 cm and r2 = 9.00 cm, what are the magnitude and (b) The direction of the net magnetic field at t

> Figure P19.64 is a setup that can be used to measure magnetic fields. A rectangular coil of wire contains N turns and has a width w. The coil is attached to one arm of a balance and is suspended between the poles of a magnet. The field is uniform and per

> Consider an electron near the Earth’s equator. In which direction does it tend to deflect if its velocity is (a) Directed downward? (b) Directed northward? (c) Directed westward? (d) Directed southeastward?

> An electron is moving at a speed of 1.0 x 104 m/s in a circular path of radius 2.0 cm inside a solenoid. The magnetic field of the solenoid is perpendicular to the plane of the electron’s path. Find (a) The strength of the magnetic field inside the solen

> Certain experiments must be performed in the absence of any magnetic fields. Suppose such an experiment is located at the center of a large solenoid oriented so that a current of I = 1.00 A produces a magnetic field that exactly cancels Earth’s 3.50 x 10

> It is desired to construct a solenoid that will have a resistance of 5.00 Ω (at 20°C) and produce a magnetic field of 4.00 x 10-2 T at its center when it carries a current of 4.00 A. The solenoid is to be constructed from copper wire having a diameter of

> A certain superconducting magnet in the form of a solenoid of length 0.50 m can generate a magnetic field of 9.0 T in its core when its coils carry a current of 75 A. The windings, made of a niobium–titanium alloy, must be cooled to 4.2 K. Find the numbe

> A long solenoid that has 1.00 x 103 turns uniformly distributed over a length of 0.400 m produces a magnetic field of magnitude 1.00 x 10-4 T at its center. What current is required in the windings for that to occur?

> In Figure P19.58 the current in the long, straight wire is I1 = 5.00 A, and the wire lies in the plane of the rectangular loop, which carries 10.0 A. The dimensions shown are c = 0.100 m, a = 0.150 m, and â„“ = 0.450 m. Find the magnitude

> A wire with a weight per unit length of 0.080 N/m is suspended directly above a second wire. The top wire carries a current of 30.0 A, and the bottom wire carries a current of 60.0 A. Find the distance of separation between the wires so that the top wire

> Two parallel wires separated by 4.0 cm repel each other with a force per unit length of 2.0 = 10-4 N/m. The current in one wire is 5.0 A. (a) Find the current in the other wire. (b) Are the currents in the same direction or in opposite directions? (c) Wh

> Two long, parallel wires separated by 2.50 cm carry currents in opposite directions. The current in one wire is 1.25 A, and the current in the other is 3.50 A. (a) Find the magnitude of the force per unit length that one wire exerts on the other. (b) Is

> Two long, parallel wires separated by a distance 2d carry equal currents in the same direction. An end view of the two wires is shown in Figure P19.54, where the currents are out of the page. (a) What is the direction of the magnetic field at P on the x

> The north - pole end of a bar magnet is held near a stationary positively charged piece of plastic. Is the plastic (a) Attracted, (b) Repelled, or (c) Unaffected by the magnet?

> The magnetic field 40.0 cm away from a long, straight wire carrying current 2.00 A is 1.00 μT. (a) At what distance is it 0.100 μT? (b) At one instant, the two conductors in a long household extension cord carry equal 2.00 - A currents in opposite direct

> A long, straight wire lies on a horizontal table in the xy - plane and carries a current of 1.20 μA in the positive x - direction along the x - axis. A proton is traveling in the negative x - direction at speed 2.30 x 104 m/s a distance d above the wire

> A wire carries a 7.00 - A current along the x - axis, and another wire carries a 6.00 - A current along the y - axis, as shown in Figure P19.51. What is the magnetic field at point P, located at x = 4.00 m, y = 3.00 m? Figure P19.51:

> Two long, parallel wires carry currents of I1 = 3.00 A and I2 = 5.00 A in the direction indicated in Figure P19.50. (a) Find the magnitude and direction of the magnetic field at a point midway between the wires (d = 20.0 cm). (b) Find the magnitude and d

> The two wires shown in Figure P19.48 are separated by d = 10.0 cm and carry currents of I = 5.00 A in opposite directions. Find the magnitude and direction of the net magnetic field (a) At a point midway between the wires; (b) At point P1, 10.0 cm to the

> A cardiac pacemaker can be affected by a static magnetic field as small as 1.7 mT. How close can a pacemaker wearer come to a long, straight wire carrying 20 A?

> In 1962 measurements of the magnetic field of a large tornado were made at the Geophysical Observatory in Tulsa, Oklahoma. If the magnitude of the tornado’s field was B = 1.50 x 10-8 T pointing north when the tornado was 9.00 km east of the observatory,

> Neurons in our bodies carry weak currents that produce detectable magnetic fields. A technique called magne-toencephalography, or MEG, is used to study electrical activity in the brain using this concept. This technique is capable of detecting magnetic f

> A long, straight wire going through the origin is carrying a current of 3.00 A in the positive z - direction (Fig. P19.44). At a point a distance r = 1.20 m from the origin on the positive x - axis, find the (a) Magnitude and (b) Direction of the magneti

> A charged particle moves in a straight line through a region of space. Which of the following answers must be true? (Assume any other fields are negligible.) The magnetic field (a) Has a magnitude of zero (b) Has a zero component perpendicular to the par

> A lightning bolt may carry a current of 1.00 x 104 A for a short time. What is the resulting magnetic field 1.00 x 102 m from the bolt? Suppose the bolt extends far above and below the point of observation.

> A rectangular loop has dimensions 0.500 m by 0.300 m. The loop is hinged along the x - axis and lies in the xy - plane (Fig. P19.42). A uniform magnetic field of 1.50 T is directed at an angle of 40.0° with respect to the positive y - axis and

> A long piece of wire with a mass of 0.100 kg and a total length of 4.00 m is used to make a square coil with a side of 0.100 m. The coil is hinged along a horizontal side, carries a 3.40 - A current, and is placed in a vertical magnetic field with a magn

> The orientation of small satellites is often controlled using torque from current - carrying coils in Earth’s magnetic field. Suppose a multi-turn coil has a cross - sectional area of 6.36 x 10-4 m2, dissipates 0.200 W of electrical power from a 5.00 - V

> A 6.00 - turn circular coil of wire is centered on the origin in the xy - plane. The coil has radius r = 0.200 m and carries a counterclockwise current I = 1.60 A (Fig. P19.39). (a) Calculate the magnitude of the coil’s magnetic moment.

> A current - carrying rectangular wire loop with width a = 0.120 m and length b = 0.200 m is in the xy - plane, supported by a non-conducting, frictionless axle of negligible weight. A current of I = 3.00 A travels counterclockwise in the circuit (Fig. P1

> An eight - turn coil encloses an elliptical area having a major axis of 40.0 cm and a minor axis of 30.0 cm (Fig. P19.37). The coil lies in the plane of the page and carries a clockwise current of 6.00 A. If the coil is in a uniform magnetic field of 2.0

> A current of 17.0 mA is maintained in a single circular loop with a circumference of 2.00 m. A magnetic field of 0.800 T is directed parallel to the plane of the loop. What is the magnitude of the torque exerted by the magnetic field on the loop?

> A wire is formed into a circle having a diameter of 10.0 cm and is placed in a uniform magnetic field of 3.00 mT. The wire carries a current of 5.00 A. Find the maximum torque on the wire.

> A horizontal power line of length 58 m carries a current of 2.2 kA as shown in Figure P19.34. Earth’s magnetic field at this location has a magnitude equal to 5.0 x 10-5 T and makes an angle of 65° with the power line. Find t

> If, in Figure 19.28, I1 = 2A and I2 = 6A, which of the following is true? (Note that F2 represents the magnitude of the force on wire 2.) (a) F1 = 3F2 (b) F1 = F2 (c) F1 = F2/3 Figure 19.28:

> In Figure P19.33, the cube is 40.0 cm on each edge. Four straight segments of wire—ab, bc, cd, and da — form a closed loop that carries a current I = 5.00 A in the direction shown. A uniform magnetic field of magnitude

> A metal rod of mass m carrying a current I glides on two horizontal rails a distance d apart. If the coefficient of kinetic friction between the rod and rails is μk, what vertical magnetic field is required to keep the rod moving at a constant speed?

> Consider the system pictured in Figure P19.31. A 15 - cm length of conductor of mass 15 g, free to move vertically, is placed between two thin, vertical conductors, and a uniform magnetic field acts perpendicular to the page. When a 5.0 - A current is di

> Mass m = 1.00 kg is suspended vertically at rest by an insulating string connected to a circuit partially immersed in a magnetic field as in Figure P19.30. The magnetic field has magnitude Bin = 2.00 T and the length â„“ = 0.500 m. (a) Fi

> A wire with a mass of 1.00 g/cm is placed on a horizontal surface with a coefficient of friction of 0.200. The wire carries a current of 1.50 A eastward and moves horizontally to the north. What are the magnitude and the direction of the smallest vertica

> At a certain location, Earth has a magnetic field of 0.60 x 10-4 T, pointing 75° below the horizontal in a north–south plane. A 10.0 - m - long straight wire carries a 15 - A current. (a) If the current is directed horizontally toward the east, what are

> A wire carries a current of 10.0 A in a direction that makes an angle of 30.0° with the direction of a magnetic field of strength 0.300 T. Find the magnetic force on a 5.00 - m length of the wire.

> A wire having a mass per unit length of 0.500 g/cm carries a 2.00 - A current horizontally to the south. What are the direction and magnitude of the minimum magnetic field needed to lift this wire vertically upward?

> In Figure P19.3, assume in each case the velocity vector shown is replaced with a wire carrying a current in the direction of the velocity vector. For each case, find the direction of the magnetic field that will produce the magnetic force shown. Figure

> A straight wire carrying a 3.0 - A current is placed in a uniform magnetic field of magnitude 0.28 T directed perpendicular to the wire. (a) Find the magnitude of the magnetic force on a section of the wire having a length of 14 cm. (b) Explain why you c

> Which of the following actions would double the magnitude of the magnetic force per unit length between two parallel current - carrying wires? Choose all correct answers. (a) Double one of the currents. (b) Double the distance between them. (c) Reduce th

> A current I = 15 A is directed along the positive x - axis and perpendicular to a magnetic field. A magnetic force per unit length of 0.12 N/m acts on the conductor in the negative y - direction. Calculate the magnitude and direction of the magnetic fiel

> In Figure P19.2, assume in each case the velocity vector shown is replaced with a wire carrying a current in the direction of the velocity vector. For each case, find the direction of the magnetic force acting on the wire. Figure P19.2:

> A particle passes through a mass spectrometer as illustrated in Figure P19.15. The electric field between the plates of the velocity selector has a magnitude of 8250 V/m, and the magnetic fields in both the velocity selector and the deflection chamber ha

> A proton (charge +e, mass mp), a deuteron (charge +e, mass 2mp), and an alpha particle (charge +2e, mass 4mp) are accelerated from rest through a common potential difference ΔV. Each of the particles enters a uniform magnetic field B(, with its velocity

> A proton is at rest at the plane vertical boundary of a region containing a uniform vertical magnetic field B (Fig. P19.19). An alpha particle moving horizontally makes a head - on elastic collision with the proton. Immediately after the collision, both

> Two long, straight wires cross each other at right angles, and each carries the same current as in Figure CQ19.18. Which of the following statements are true regarding the total magnetic field at the various points due to the two wires? (There may be mor

> Jupiter’s magnetic field occupies a volume of space larger than the Sun and contains ionized particles ejected from sources including volcanoes on Io, one of Jupiter’s moons. A sulfur ion (S+) in Jupiter’s magnetic field has mass 5.32 x 10-26 kg and kine

> Figure CQ19.16 shows four permanent magnets, each having a hole through its center. Notice that the blue and yellow magnets are levitated above the red ones. (a) How does this levitation occur? (b) What purpose do the rods serve? (c) What can you say abo

> Consider the mass spectrometer shown schematically in Figure P19.15. The electric field between the plates of the velocity selector is 9.50 x 102 V/m, and the magnetic fields in both the velocity selector and the deflection chamber have magnitudes of 0.9

> How can a current loop be used to determine the presence of a magnetic field in a given region of space?

> A square and a circular loop with the same area lie in the xy - plane, where there is a uniform magnetic field B( pointing at some angle θ with respect to the positive z - direction. Each loop carries the same current, in the same direction. Which magnet

> An electron moves in a circular path perpendicular to a magnetic field of magnitude 0.235 T. If the kinetic energy of the electron is 3.30 x 10-19 J, find (a) The speed of the electron and (b) The radius of the circular path.

> Why do charged particles from outer space, called cosmic rays, strike Earth more frequently at the poles than at the equator?

> At the equator, near the surface of Earth, the magnetic field is approximately 50.0 μT northward, and the electric field is about 100. N/C downward in fair weather. Find the gravitational, electric, and magnetic forces on an electron with an instantaneou

> Is the magnetic field created by a current loop uniform? Explain.

> A proton moving at 4.00 x 106 m/s through a magnetic field of magnitude 1.70 T experiences a magnetic force of magnitude 8.20 x 10-13 N. What is the angle between the proton’s velocity and the field?

> A magnet attracts a piece of iron. The iron can then attract another piece of iron. On the basis of domain alignment, explain what happens in each piece of iron.

> Electrons and protons travel from the Sun to the Earth at a typical velocity of 4.00 x 105 m/s in the positive x - direction. Thousands of miles from Earth, they interact with Earth’s magnetic field of magnitude 3.00 x 10-8 T in the positive z - directio

> Will a nail be attracted to either pole of a magnet? Explain what is happening inside the nail when it is placed near the magnet.

> A laboratory electromagnet produces a magnetic field of magnitude 1.50 T. A proton moves through this field with a speed of 6.00 x 106 m/s. (a) Find the magnitude of the maximum magnetic force that could be exerted on the proton. (b) What is the magnitud

> Can a constant magnetic field set a proton at rest into motion? Explain your answer.

> As a charged particle moves freely in a circular path in the presence of a constant magnetic field applied perpendicular to the particle’s velocity, the particle’s kinetic energy (a) Remains constant, (b) Increases, or (c) Decreases.

> The circuit in Figure P18.62 contains two resistors, R1 = 2.0 kΩ and R2 = 3.0 kΩ, and two capacitors, C1 = 2.0 μF and C2 = 3.0 μF, connected to a battery with emf ε = 120 V. If there are no