Some charged particles are suspended inside a hollow metal object by supports made of a material that is an electrical insulator. The metal object has charge +q distributed over its outer surface and charge ?2q distributed over its inner surface. A. How much charge is suspended in the cavity?

B. What is the charge on the object? (Hint: What is the electric field a very large distance r from the center of the object?)

We will use a video to study faraday’s law of electromagnetic induction by analyzing the induction that occurs due a coil of copper wire sliding along an air track that passes through an external magnetic field. specifically, we will: examine some of the main principles behind faraday’s law. apply lenz’s law to determine the direction of the induced emf. take measurements of the induced emf from the voltmeter as the coil passes into and out of the external magnetic field. use the horizontal scale provided to determine the speed of the coil. calculate the magnetic field induced in the coil as it passes into and out of the external magnetic field.