5. What's the time constant of a circuit made up of a 1,000 resistor connected in series with a 1 mH inductor? O A. 10 sec
OB. 100 usec
O C. 1 usec
O D. 5 usec

On solidification from a melt, the polymer polyethylene forms a semi-crystalline spherulite structure. (i) sketch an individual spherulite and label the amorphous and crystalline regions. (ii) draw a schematic to show the changes in specific volume with temperature during cooling from the melt, comparing it to the theoretical extremes of fully crystalline and fully amorphous (indicate tm and tg)