Selected Problems from Chapters 29 & 30

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Consider a plane square loop made of 1.0 m long wire in a uniform magnetic field of 1.5 T. The magnetic field is directed perpendicular to the yz-plane. If the plane of the loop makes an angle of 30 o with the direction of the magnetic field, find the magnetic flux passing through the loop. A) T ⋅ m2. B) T ⋅ m2. C) 0.75 T ⋅ m2. D) 1.3 T ⋅ m2. E) T ⋅ m2. a = 1/4 m A 30 o 60 o B

A long straight wire is in the plane of two circular conducting loops. The straight wire carries a constant current I in the direction shown in Fig 9. The circular loop 1 is moved to the right while the loop 2 is moved to the left with the same speed, v. The induced current directions in the circular loops 1 and 2 are respectively: A) Clockwise, counterclockwise B) Clockwise, clockwise C) Counterclockwise, clockwise D) Counterclockwise, counterclockwise E) No current in both the loops

The figure shows two loops and a long straight wire lying in the same plane. If the current in the straight wire is increased, then A) The induced current in loop 1 is counterclockwise and in loop 2 is clockwise. B) The induced current in loop 1 is clockwise and in loop 2 is counterclockwise. C) In both loops, the induced current is clockwise. D) In both loops, the induced current is counterclockwise. E) In both loops, there is no induced current. Loop 1 Loop 2

Consider a rectangular conducting loop of length a = 20 cm and width b = 10 cm and resistance R = 10 Ω as shown in the figure. The loop is moving out of a uniform magnetic field region, at a constant speed of 5.0 m/s. The magnetic field B is into the page and has a magnitude of 0.50 T. What is the magnitude and direction of the induced current? A) 25 mA clockwise B) 25 mA counterclockwise C) 30 mA clockwise D) 30 mA counterclockwise E) 20 mA clockwise x

A 2.0 m long copper wire, with resistance 5.0 Ω, is shaped into a square loop and placed perpendicular to a uniform magnetic field that is increasing at the constant rate of 1.0 ×10 -2 T/s. At what rate is thermal energy generated in the loop? A) 1.3 x10-6 W. B) 4.5 x10-6 W. C) 3.2 x10-6 W. D) 2.1 x10-4 W. E) 1.1 x10-7 W.