Abug zapper consists of two metal plates connected to a high-voltage power supply. the voltage between the plates is set to give an electric field slightly less than 1×10^6 v/m. when a bug flies between the two plates, it increases the field enough to initiate a spark that incinerates the bug.
if a bug zapper has a 7000 v power supply, what is the approximate separation between the plates?

(a) 7×10-2 cm
(b) 0.7 cm
(c) 7 cm
(d) 70 cm

Which of the following changes to a pipe would increase the conductance by a factor of 12? 1.quadrupling the length and tripling the radius.2.reducing the length by a factor of and doubling the radius.3.tripling the length and reducing the radius by a factor of .4.reducing the length but a factor of and doubling the radius.

Copper has free electrons per cubic meter. a 71.0-cm length of 12-gauge copper wire that is 2.05 mm in diameter carries 4.85 a of current. (a) how much time does it take for an electron to travel the length of the wire? (b) repeat part (a) for 6-gauge copper wire (diameter 4.12 mm) of the same length that carries the same current. (c) generally speaking, how does changing the diameter of a wire that carries a given amount of current affect the drift velocity of the electrons in the wire?

50 g of ice at 0°c is dropped in a beaker containing 100 g of water at 0°c. what will be the contents of the beaker after 5 hours? assume that the room temperature is 0°c.