Acapacitor c is connected in series with a resistor r across a battery and an open switch. if a second capacitor of capacitance 2c is connected in parallel with the first one, the time constant of the new rc circuit will be

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

Consider the growth of a 20-nm-diameter silicon nanowire onto a silicon wafer. the temperature of the wafer surface is maintained at 2400 k. assume the thermal conductivity of the silicon nanowire is 20 wm-1k-1 and all its surfaces including the tip are subjected to convection heat transfer with the coefficient h = 1×105 wm-2k-1 and t∞ = 8000 k. when the nanowire grows to l = 300 nm, what is the temperature of the nanowire tip (t (x =

Abowling ball rolling down the lane toward the pins has gravitational potential energy. a. no b. a lot of c. a little