# Magnetic Flux and Induction Problems

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1) A 0.50 T magnetic field is directed perpendicular to the plane of a circular loop of radius 0.25 m. What is the magnitude of the magnetic flux through the loop?

0.098 Wb

2) The Earth’s magnetic field passes through a square tabletop with a magnitude of 4.95 x 10-5T and directed at an angle of 165o relative to the normal of the tabletop. If the tabletop has 1.50 m sides, what is the magnitude of the magnetic flux through it?

1.08 x 10-4 Wb

3) A conducting loop has an area of 0.065 m and is positioned such that a uniform magnetic field is perpendicular to the plane of the loop. When the magnitude of the magnetic field decreases to 0.30 T in 0.087 s, the average induced emf in the loop is 1.2 V. What is the initial value of the magnetic field?

1.9 T

4) A magnetic field is directed perpendicular to the plane of the 0.15 m x 0.30 m rectangular coil comprised pf 120 loops of wire. To induce an average emf of -1.2 V in the coil, the magnetic field is increased from 0.1 T to 1.5 T during a time interval Δt. Determine Δt.

6.3 s

5) A 150 turn solenoid carries a current of 12 A. The radius of the solenoid is 0.050 m and its length is 0.18 m. Determine the magnetic flux through the circular cross-sectional area at the center of the solenoid.

9.9 x 10-5 Wb

6) A flat coil with radius 8.0 mm has 50 loops of wire. It is placed in a magnetic field B =0.30 T in such a way that the maximum flux goes through it. Later, it is rotated in 0.02s to a position such that no flux goes through it. Find the average emf induced between the terminals of the coil.

0.15 V