Find the electric field a distance z above a circular ring carrying a constant line charge. For extra credit you may derive the electric field a distance z above a disk carrying a constant surface charge density. 3 Find the force between an electron and a proton in a typical hvdrogen atom.

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What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?

Which of the following is a characteristic shared by both electron and light microscopes? a. they both employ the use of objective lenses. b. both microscopes require an internal camera to visualize the specimen. c. both microscopes have a resolving power of 0.01 nm. d. they both utilize white light to magnify the specimen.