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A 25-turn circular coil of wire has diameter 1.00 m. It is placed with its axis along the direction of the Earth's magnetic field of 50.0 μT, and then in 0.200 s it is flipped 180°. An average emf of what magnitude is generated in the coil?


The magnetic field perpendicular to a circular loop of wire 17.6cm in diameter is changed from +0.510 T to -0.450 T in 117rms, where + means the field points away from an observer and - toward the observer. Calculate the induced emf.

Magnetic field : key information

A 6.30cm diameter wire coil is initially oriented so that its plane is perpendicular to a magnetic field of 0.740T pointing up. During the course of 0.130s, the field is changed to one of 0.310 T pointing down. What is the average induced emf in the coil?

bar sliding in a magnetic field on rails - Voltage induced

Imagine that we have two metal rails 20 cm apart connected by a light bulb. The rails are placed in a 1.0 T magnetic field oriented vertically downward. We then constrain a bar to slide on the rails toward the lightbulb in this magnetic field. How fast do we have to move the bar to put a voltage difference of 3.0 V across the

current in a 48.1 mH inductor changes with time

The current in a 48.1 mH inductor changes with time as I = bt^2 - at. With a = 2.7 A/s and b = 3 A/s^2, find the magnitude of the induced emf at t = .992 s. Units of V At what time is the emf zero? Units of s

Batteries and Circuits

PART ONE: A battery that supplies an emf of 6.0 V has an internal resistance of 0.20 ohm. It is connected to a load resistor of 8.8 ohms. The total Current in the entire circuit is: A) less than 0.25 A B) between 0.25 A and 0.50 A C) between 0.50 A and 1.0 A D) greater than 1.0 A PART TWO: A battery of fou

Calculating the induced emf.

The length of a conductor linking a magnetic field is 0.060m, and the flux density of the field is 0.040 N/Am The conductor is moving down through the flux with a velocity of 1.5 m/s. What is the induced emf?

Electromagnetic theory

A circular current loop made of flexible wire is located in a magnetic field B; you may keep B constant or vary it. Describe three ways an emf can be induced in the loop.

Calculate the self-inductance of the coil and the emf induced in it.

A coil of 500 turns is wound on a wooden ring having a mean diameter of 8 cm and a cross sectional area of 1.5 cm^2. Assuming relative permeability of wood is 1, calculate the self-inductance of the coil and the emf induced in it when the direction of a DC current of 5A flowing in it is reversed in 0.2 sec?