A metal sphere with radius ra = 1.30 cm is supported on an insulating stand at the center of a hollow, metal, spherical shell with radius rb = 9.30 cm . Charge +q is put on the inner sphere and charge −q on the outer spherical shell. The magnitude of q is chosen to make the potential difference between the spheres 440 V , with the inner sphere at higher potential. Are the electric field lines and equipotential surfaces mutually perpendicular?

Abeam of electrons with of wavelength of 7.5 x 10-6 m is incident on a pair of narrow rectangular slits separated by 0.75 mm. the resulting interference pattern is projected onto a screen 10.0 m from the slits. what is the separation of the interference maxima in the resulting interference pattern?

Choose a synonym for the underlined homonym (a word with two or more meanings). i did not expect the boat to rock so much. a. boulder c. astound b. sway d. shock

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.