Exam 29: The Magnetic Field

The figure shows a velocity selector that can be used to measure the speed of a charged particle.A beam of particles is directed along the axis of the instrument.A parallel plate capacitor sets up an electric field E,which is oriented perpendicular to a uniform magnetic field B.If the plates are separated by 2.0 mm and the value of the magnetic field is 0.60 T,what voltage between the plates will allow particles of speed 5.0 × 10⁵ m/s to pass straight through without deflection?

The figure shows three long,parallel,current-carrying wires.The current directions are indicated for currents I₁ and I₃.The arrow labeled F represents the net magnetic force acting on current I₃.The three currents have equal magnitudes.What is the direction of the current I₂?

A wire segment 1.2 m long carries a current I = 3.5 A and is oriented as shown in the figure.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.The +z-axis points directly into the page.What is the magnetic force vector on the wire segment?

A charged particle of mass 0.0020 kg is subjected to a magnetic field which acts at a right angle to its motion.If the particle moves in a circle of radius at a speed of what is the magnitude of the charge on the particle?

Two long parallel wires carry currents of 10 A in opposite directions.They are separated by 40 cm.What is the magnitude of the magnetic field in the plane of the wires at a point that is 20 cm from one wire and 60 cm from the other? (μ₀ = 4π × 10^-7 T ∙ m/A)

As shown in the figure,an insulated wire is bent into a circular loop of radius 6.0 cm and has two long straight sections.The loop is in the xy-plane,with the center at the origin.The straight sections are parallel to the z-axis.The wire carries a current of 8.0 A.What is the magnitude of the magnetic field at the origin? (μ₀ = 4π × 10^-7 T ∙ m/A)

A negatively charged particle is moving to the right,directly above a wire having a current flowing to the right,as shown in the figure.In which direction is the magnetic force exerted on the particle?

A hollow cylinder with an inner radius of and an outer radius of conducts a 3.0-A current flowing parallel to the axis of the cylinder.If the current density is uniform throughout the wire,what is the magnitude of the magnetic field at a point from its center? (μ₀ = 4π × 10^-7 T ∙ m/A)

A rectangular loop of wire carrying a 4.0-A current is placed in a magnetic field of 0.60 T.The magnitude of the torque acting on this wire when the plane of the loop makes a 30° angle with the field is measured to be 1.1 N ∙ m.What is the area of this loop?

An electron moving with a velocity = 5.0 × 10⁷ m/s enters a region of space where perpendicular electric and a magnetic fields are present.The electric field is = .What magnetic field will allow the electron to go through the region without being deflected?

A tube with a 3.0-mm radius has ions flowing through it along its length.To determine the rate at which the charge is being moved through the tube,the magnetic field just outside the tube is measured and found to be If the only contributor to the magnetic field is the moving ions,and if the walls of the container are very thin and do not screen magnetism,what is the magnitude of the current flowing through the tube? (μ₀ = 4π × 10^-7 T ∙ m/A)

A proton is first accelerated from rest through a potential difference V and then enters a uniform 0.750-T magnetic field oriented perpendicular to its path.In this field,the proton follows a circular arc having a radius of curvature of 1.84 cm.What was the potential difference V? (m_proton = 1.67 × 10^-27 kg,e = 1.60 × 10^-19 C)

As shown in the figure,a rectangular current loop is carrying current = 3.0 A,in the direction shown,and is located near a long wire carrying a current .The long wire is parallel to the sides of the rectangle.The rectangle loop has length 0.80 m and its sides are 0.10 m and 0.70 m from the wire,as shown.We measure that the net force on the rectangular loop is and is directed towards the wire.(μ₀ = 4π × 10^-7 T ∙ m/A) (a)What is the magnitude of the current I_w? (b)In which direction does I_w flow: from top to bottom or from bottom to top in the sketch?

As shown in the figure,a small particle of charge q = -7.0 × C and mass has velocity as it enters a region of uniform magnetic field.The particle is observed to travel in the semicircular path shown,with radius R = 5.0 cm.Calculate the magnitude and direction of the magnetic field in the region.

A very long straight wire carries a 12-A current eastward and a second very long straight wire carries a 14-A current westward.The wires are parallel to each other and are 42 cm apart.Calculate the force on a 6.4 m length of one of the wires.(μ₀ = 4π × 10^-7 T ∙ m/A)

A uniform magnetic field of magnitude 0.80 T in the negative z-direction is present in a region of space,as shown in the figure.A uniform electric field is also present.An electron that is projected with an initial velocity in the positive x-direction passes through the region without deflection.What is the electric field vector in the region?

Two coaxial circular coils of radius R = 15 cm,each carrying 4.0 A in the same direction,are positioned a distance d = 20 cm apart,as shown in the figure.Calculate the magnitude of the magnetic field halfway between the coils along the line connecting their centers. (μ₀ = 4π × 10^-7 T ∙ m/A)

As shown in the figure,two long straight wires are separated by a distance of The currents are to the right in the upper wire and to the left in the lower wire.What are the magnitude and direction of the magnetic field at point P,which is a distance below the lower wire? (μ₀ = 4π × 10^-7 T ∙ m/A)

A long straight conductor has a constant current flowing to the right.A wire rectangle is situated above the wire,and also has a constant current flowing through it (as shown in the figure).Which of the following statements is true?

A particle with charge -5.00 C initially moves at = (1.00 + 7.00 )m/s.If it encounters a magnetic field find the magnetic force vector on the particle.