A circular coil of wire with radius 5cm and 25 turns is placed in a uniform magnetic field of magnitude 0.2 T. The magnetic field is parallel to the area vector; i.e. perpendicular to the plane of the coil. a) What is the magnetic flux through the coil? b) The magnetic field is decreased to 0 T in 0.1 s. What is the magnitude of the emf induced in the coil during this time interval? c) If the coil has a resistance per unit length of 2 /m, how much current flows in the coil during this time interval? Please write your answers in the space below and email your work. For the toolbar, press ALT+F10 (PC) or ALT+FN+F10 (Mac).

A coil is placed in a uniform constant external magnetic field directed perpendicular to the plane of the coil. Which of the following actions would not induce an emf in the coil? a) Rotating the coil to change the angle ϕ b) Changing the strength of the magnetic field. c) Moving the entire coil in a direction parallel to the direction of the magnetic field d) Reducing the radius of the coil.

A helicopter (see figure below) has blades of length 2.80 m; extending out from a central hub and rotating at 3.40 rev/s. If the vertical component of the Earth's magnetic field is 50.0 μT, what is the magnitude of emf induced between the blade tip and the center hub? mV Sascha Hahn/Shutterstock.com

The component of the external magnetic field along the central axis of a 69 turn circular coil of radius 47.0 cm decreases from 2.90 T to 0.700 T in 2.10 s. If the resistance of the coil is R = 3.00 §, what is the magnitude of the induced current in the coil? magnitude: What is the direction of the current if the axial component of the field points away from the viewer? counter-clockwise clockwise A

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C 12:52 HW8_60e193652a3a1c9d2d... 2. 2 of 4 SOS Done The 5.2 m long metal rotor blades of a helicopter spin at 6.0 revolutions per second perpendicular to the earth's magnetic field of 4.7x10 T. Axis What is the magnetic flux swept out by the rotor blades in one revolution and what is the emf induced between the axis and tip of a rotor blade? 3. In a CRT electrons are accelerated from rest by a potential difference of 1.40x10'V These electrons enter a magnetic field with a strength of 2.20x102 T Assuming the electrons are traveling perpendicular to the field what id the radius of the are of the deflected electrons?

= A single-turn circular loop has a radius of 25 cm, it is placed in a magnetic field of B 3.5 T which is perpendicular to the plane of the loop, see the figure below. The loop is reshaped into a perfect square without stretching the length of the loop. It takes 0.43 s to reshape the loop. What is the magnetic flux through the loop before and after it is reshaped? B X X X X X X X X X X X X X x x The final flux, Of = 5 x X X X X X X The initial flux, ¡ = 0.0000006 X Units mWb Х Х The induced emf, Emf = 34 X Units mWb x X X X What is the magnitude of the average induced emf in the loop during the reshaping process? X Units mV хх Question Help: Message instructor Post to forum

A 19-turn circular coil of wire has diameter 0.95 m. It is placed with its axis along the direction of the Earth's magnetic field of 44.0 μT and then in 0.200 s is flipped 180°. An average emf of what magnitude is generated in the coil? mV Need Help? Read It Watch It