Parallel rays from a distant object are traveling in air and then are incident on the concave end of a glass rod with a radius of curvature of 15.0 cm. The refractive index of the glass is 1.50. What is the distance between the vertex of the glass surface and the image formed by the refraction at the concave surface of the rod? Is the image in the air or in the glass?

Which type of circuit is becoming more common in residential electrical design and construction? a. hazardous-area circuit b. three-phase circuit c. 480-volt circuit d. communication circuit

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.

The 5-kg cylinder is initially at rest when it is placed in contact with the wall b and the rotor at a. if the rotor always maintains a constant clockwise angular velocity v = 6 rad> s, determine the initial angular acceleration of the cylinder. the coefficient of kinetic friction at the contacting surfaces b and c is mk = 0.2.