Two boxes, connected by a cord, are pulled horizontally on a frictionless surface with an applied force of 40.0 N. Box A has a
mass of 10.0 kg; Box B has a mass of 12.0 kg.
(Hint: you have Fn & Fg for BOTH vertically, you have decide on the horizontal forces.)
a. Draw a free body diagram for box A.
b. Draw a free body diagram for box B.
c. Find the acceleration, a, of the two boxes.
d. Find the tension, FT, in the cord connecting boxes A and B

Athin electrical heater is inserted between a long circular rod and a concentric tube with inner and outer radii of 20 and 40 mm. the rod (a) has a thermal conductivity of ka = 0.15 w/(m*k), while the tube (b) has a thermal conductivity of kb = 0.8 w/(m*k) and its outer surface is subjected to convection with a fluid of temperature t= -15°c and heat transfer coefficient 60 w/(m2 *k). the thermal contact resistance between the cylinder surfaces and the heater is negligible. (a) determine the electrical power per unit length of the cylinders (w/m) that is required to maintain the outer surface of cylinder b at 15°c. (b) what is the temperature at the center of cylinder a?