Prior to 1960, magnetic field strengths were usually measured by a rotating coil gaussmeter. This device used a small, multi-turn coil rotating at a high speed on an axis perpendicular to the magnetic field. The coil was connected to an ac voltmeter by means of slip rings. In one specific design, the rotating coil has 400 turns and an area of 1.4 cm2 . The coil rotates at 180 rev/min. If the magnetic field strength is 0.450T, find the maximum induced emf in the coil and the orientation of the normal to the plane of the coil relative to the field for which this maximum induced emf occurs.

Na food processing facility, a spherical container of inner radius r1 5 40 cm, outer radius r2 5 41 cm, and ther- mal conductivity k 5 1.5 w/m · k is used to store hot water and to keep it at 100°c at all times. to accomplish this, the outer surface of the container is wrapped with a 800-w electric strip heater and then insulated. the temperature of the inner surface of the container is observed to be nearly 120°c at all times. as- suming 10 percent of the heat generated in the heater is lost through the insulation, (a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the container, (b) obtain a relation for the variation of temperature in the container material by solving the differential equation, and (c) evaluate the outer surface tempera- ture of the container. also determine how much water at 100°c this tank can supply steadily if the cold water enters at 20°c.

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer

What is the orbital period of a spacecraft in a low orbit near the surface of mars? the radius of mars is 3.4×106m.