S123 Physics for Engineers (Lecture) | Final Examination 1. Accomplished silver workers in India can pound silver into incredibly thin sheets, as thin as 3 * 10 ^ - 7 m (about one-hundredth of the thickness of this sheet of paper). Find the area a sheet that can be formed from 1 kg of silver. (Note: density of silver is 10.5kg / (m ^ 3) ) (1.5pts) 2. A patient recovering from surgery given fluid intravenously. The fluid has a density of 1030kg / (m ^ 3) and overline 9 * 0.5 * 10 ^ - 4 * m ^ 3 of it flows into the patient every six hours. Find the mass flow rate in kg / s * (20pcs) 3. In an electrically heated home, the temperature of the ground in contact with the concrete basement wall is 12.8°C. The temperature at the inside surface of the wall is 20°C. The wall is 0.10 m thick and has an area of 9m ^ 2 Assume that one killowarr-hour of electrical energy costs 0.10 dollars. How many hours are required for one dollar's worth of energy to be conducted through the wall? (Note: use k=1.1 J/(s* m*^ C) (30p + s) 4. To navigate, a porpoise emits a sound wave that has a wavelength of 1.5 cm. The speed at which the wave travels in seawater is 1522 m/s. Find the period of the wave. (15pts) 5. A long solenoid has 1400 turns per meter of length, and it carries a current of 3.5 A. A small circular coil of wire is placed inside the solenoid with the normal to the coil oriented at an angle of 90.0° with respect to the axis of the solenoid. The coil consists of 50 turns, has an area of 1.2 * 10 ^ - 3 * m ^ 2 and carries a current of 0.50 A. Find the torque exerted on the coil. (20pts)