An L = 51.0 cm wire is moving to the right at a speed of U = 7.50 m/s across two parallel wire rails that are connected on the left side, as shown in the figure. The whole apparatus is immersed in a uniform magnetic field that has a magnitude of B = 0.750 T and is directed into the screen. What is the emf E induced in the wire? V The induced emf causes a current to flow in the circuit formed by the moving wire and the rails. In which direction does the current flow around the circuit? O clockwise counterclockwise 8)

A straight conductor of length I moves with an acceleration a = 0.1 ms2 at right angles to a magnetic field of uniform strength B = 10 T. The e.m.f. between the ends of the conductor increased from 0 to 5 V during the first 20 s after the beginning of motion. Calculate I and give your answer in SI units.

Two coils with iron cores are positioned as shown in the figure. The smaller coil is part of a circuit with a battery and a switch. Immediately after the switch Sis closed, which one of the following statements is true? O A magnetic field that points away from the smaller coil appears inside the larger coil. O An induced current will flow from right to left in R. O A magnetic field that points away from the larger coil appears inside the smaller coil. O A current will pass through r, but there will be no current through R. O An induced current will flow from left to right in R.

I want to generate an average emf of 10 V with a circular coil of wire with diameter 10 cm and 500 coils. How much time should I take to rotate the coil 90 degrees if the coil is in a magnet field of magnitude 9e-3 T? The loop starts flat on the xy plane and the magnetic field at this time is pointed in the positive x direction. The loop rotates about the y-axis. a) 0.00353 s b) 283.32 s c) 7.06E-6 s d) 3.54E-6 s

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Suppose a magnetic field B(t) oscillates with frequency w. A circular loop of copper lies perpendicular to the magnetic field. The radius of the circular loop is r. a. Write down an expression for the magnetic field as a function of time. Determine the induced emf & in the loop of wire and use this to calculate the current generated in the loop as a function of time. b. What is the power dissipation in the wire as a function to time? Make a sketch of this function. What is the average power Pave dissipation in the wire? Hint: what is the average value of the function you sketched? C. Recall that power is a rate of energy transfer, and that power dissipated by a resistor leads to a change in the thermal energy of the material (in this case the copper wire). We can relate a change in thermal energy to a change in temperature by AT where M is the total mass and c ΔΕth Mc is the specific heat capacity of the material (see page 526 for details). Find an expression for a dT - differential…

A single loop of copper wire, lying flat in a plane, has an area of 8.40 cm² and a resistance of 1.80 . A uniform magnetic field points perpendicular to the plane of the loop. The field initially has a magnitude of 0.500 T, and the magnitude increases linearly to 2.00 T in a time of 1.08 s. What is the induced current (in mA) in the loop of wire over this time? mA Need Help? Read It

A 24-turn circular coil of wire has diameter 1.09 m. It is placed with its axis along the direction of the Earth's magnetic field of 47.0 µT and then in 0.200 s is flipped 180°. An average emf of what magnitude is generated in the coil? x What is the change in the magnetic flux during this time interval? mV

A coil formed by wrapping 55 turns of wire in the shape of a square is positioned in a magnetic field so that the normal to the plane of the coil makes an angle of 36.0° with the direction of the field. When the magnetic field is increased uniformly from 200 µT to 600 µT in 0.400 s, an emf of magnitude 80.0 mV is induced in the coil. What is the total length of the wire? m

The figure below shows a flexible loop of metal wire with a radius of 15.0 cm. It lies in a magnetic field pointing into the page with a magnitude of 0.140 T. A physicist grabs the loop at points A and B and rapidly pulls in opposite directions until the loop folds up, such that its area becomes zero. The change in area occurs in a span of 0.190 s. A What is the average induced emf (in mV) in the loop over this time span? mv