Asteady voltage source v = 1 v is connected to a coil which consists of a 50 m length of copper wire of radius 0.01 mm. given that the number density of mobile electrons in copper is 8.5 x 1022 cm-3 and p= 1.72 x 10-82 m, calculate: (a) the electric field e which acts on the mobile electrons in the coil. (b) the drift velocity v of the mobile electrons. (c) the resistance r of the coil. (d) the steady dc current i in the coil. (ans: 0.02 v m-! ; 8.6 x 10-5 m sl; 2738 w; 0.36 ma)

On a hot saturday morning while people are working inside, the air conditioner keeps the temperature inside the building at 22degreesc. at noon the air conditioner is turned off, and the people go home. the temperature outside is a constant 33degreesc for the rest of the afternoon. if the time constant for the building is 4 hr, what will be the temperature inside the building at 4 : 00 font size decreased by 2 upper p . font size decreased by 2 upper m .? at 6 : 00 font size decreased by 2 upper p . font size decreased by 2 upper m .? when will the temperature inside the building reach 24degreesc? 324281