Physics Exam #2-Chapter 22-Practice Problems

A one-turn circular coil is made from a wire that has a length of 7.00 10-2 m. If the coil is placed in a uniform magnetic field of 4.95 T and the current in the coil is 2.60 A, determine the maximum torque experienced by this coil.

.0050 N*m

If a single circular loop of wire carries a current of 77 A and produces a magnetic field at its center with a magnitude of 2.30 10-4 T, determine the radius of the loop.

0.211 m

A proton moves at 7.80 ✕ 107 m/s perpendicular to a magnetic field. The field causes the proton to travel in a circular path of radius 0.830 m. What is the field strength (in T)?

0.98 T

A charged particle moving through a magnetic field at right angles to the field with a speed of 24.7 m/s experiences a magnetic force of 2.18 10-4 N. Determine the magnetic force on an identical particle when it travels through the same magnetic field with a speed of 4.34 m/s at an angle of 21.2° relative to the magnetic field.

1.38e-5 N

A wire carrying a 28.0 A current passes between the poles of a strong magnet perpendicular to its field and experiences a 2.20 N force on the 4.00 cm of wire in the field. What is the average field strength (in T)?

1.96 T

A current-carrying wire passes through a region of space that has a uniform magnetic field of 0.79 T. If the wire has a length of 2.9 m and a mass of 0.74 kg, determine the minimum current needed to levitate the wire.

3.16 A

A cosmic ray electron moves at 7.85 ✕ 106 m/s perpendicular to the Earth's magnetic field at an altitude where field strength is 1.20 ✕ 10−5 T. What is the radius (in m) of the circular path the electron follows?

3.72 m

At what speed (in m/s) will a proton move in a circular path of the same radius as an electron that travels at 7.15 ✕ 106 m/s perpendicular to the Earth's magnetic field at an altitude where the field strength is 1.25 ✕ 10−5 T? B. What would the radius (in m) of the path be if the proton had the same speed as the electron? C. What would the radius (in m) be if the proton had the same kinetic energy as the electron? D. What would the radius (in m) be if the proton had the same momentum as the electron?

3894 m/s B = 5985 m C = 139 m D = 3.25 m

Find the current (in A) through a loop needed to create a maximum torque of 7.00 N · m. The loop has 51 square turns that are 16.0 cm on a side and is in a uniform 0.900 T magnetic field.

5.96 A

A rectangular coil with a length of 6.0 cm and a width of 4.0 cm and 250 turns is placed in a uniform magnetic field with a magnitude of 0.91 T. A. If the maximum torque experienced by the coil is 0.25 N · m, determine the current in the coil. B. When the magnetic field makes an angle of 35° with the normal to the plane of the coil, determine the magnitude of the torque acting on the coil.0.146 N · m

A = 0.31 A B = 0.146 N*m

An electron moving at 4.00×103 m/s in a 1.25-T magnetic field experiences a magnetic force of 1.40×10−16 N . What angle does the velocity of the electron make with the magnetic field?

Angle: 10.1 degrees

magnitude: 8.52 uT direction: 90 degrees

As shown in the figure below, two long parallel wires (1 and 2) carry currents of I1 = 2.82 A and I2 = 4.95 A in the direction indicated. (a) Determine the magnitude and direction of the magnetic field at a point midway between the wires (d = 10.0 cm).

A DC power line for a light-rail system carries 1000 A at an angle of 30.0° to the Earth's 5.00×10−5 -T field. What is the force on a 100-m section of this line?

F = 2.5 N

A 0.750-m-long section of cable carrying current to a car starter motor makes an angle of 60o with the Earth's 5.50×10−5 T field. a. What is the current when the wire experiences a force of 7.00×10−3 N ? b. If you run the wire between the poles of a strong horseshoe magnet, subjecting 5.00 cm of it to a 1.75-T field, what force is exerted on this segment of wire?

I = 196 A F= 17.2

Find the current in a long straight wire that would produce a magnetic field twice the strength of the Earth's at a distance of 5.0 cm from the wire. Earth's field is about 5.0 × 10−5T.

I = 25 A

A coil of wire has an area of 2.0x10-4m2, consists of 100 loops or turns, and contains a current of 0.045 A. The coil is placed in a uniform magnetic field of magnitude 0.15 T. (a) Determine the magnetic moment of the coil. (b) Find the maximum torque that the magnetic field can exert on the coil.

NIA (magnetic moment) = 9.0 10 A m^2 maximum torque = 1.4 10 N m

A cosmic ray electron moves at 7.50×106 m/s perpendicular to the Earth's magnetic field at an altitude where field strength is 1.00×10−5 T . What is the radius of the circular path the electron follows?

r = 4.27 m