2. Three blocks with masses m1= 2.0 kg, m2 = 4.0 kg and m3 = 3.0 kg are placed side by side on a table. The friction between the blocks and the table is negligible. A constant force with magnitude F = 18 N is
applied to the left-most block. (a) Find the acceleration of the system of three blocks. (b) Find the contact
force between the left-most block and the middle block. (c) Find the contact force between the middle block
and the right-most block. (6 points)
ml
m2
m3

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.