4.A medical process called magnetic resonance imaging (MRI) replaced X-rays in some instances where pictures are required to study soft internal organs. Nancy is undergoing an MRI procedure and is placed inside a chamber housing the coil of a large electromagnet that has a radius of 25.0 cm. A flux of 0.290 Wb passes through the coil. What is the strength of the magnetic field inside the coil? 8) A 2.5 Watts (Power=Current*Voltage) wire is curled into an elliptical loop with an area of 1.2 m^2 and is placed horizontally on a table where it is embedded in a 30 mT magnetic field that points upward. The ends of the ellipse are then pulled, stretching it out and reducing the area to 0.1 m^2. As the ellipse narrows, a current of 3.6 mA is generated in the wire. How long does it take to change the ellipse's shape? With the Power and the current, you can find the voltage. Then you can use the equation for induced voltage that we learned in class today.
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The magnetic flux (Φ) through a coil is given by the product of the magnetic field strength (B), the area of the coil (A), and the cosine of the angle between the magnetic field and the normal to the coil (cosθ). In this case, the magnetic field is perpendicular Show more…
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