A 2.10 mH toroidal solenoid has an average radius of 5.80 cm and a cross-sectional area of 2.20 cm^2 .

A. How many coils does it have? In calculating the flux, assume that B is uniform across a cross section, neglect the variation of B with distance from the toroidal axis

B. At what rate must the current through it change so that a potential difference of 2.40 V is developed across its ends?

Which of the following is not am example of a polymer? protein nylon kevlar concreta

It is really hard for me right know

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.