Two extremely large nonconducting horizontal sheets each carry uniform charge density on the surfaces facing each other. the upper sheet carries +5.00 µc/m2. the electric field midway between the sheets is 4.25 × 105 n/c pointing downward. what is the surface charge density on the lower sheet? (ε0 = 8.85 × 10-12 c2/n · m2)

Comedians like to joke that the reason we haven’t been visited by intelligent life from elsewhere in the universe is that aliens have been monitoring earth’s broadcasts of intellectually embarrassing tv programs, like gilligan’s island, fear factor, the jersey shore, and the jerry springer showand so consider us far too primitive to merit a visit. let’s check the assertion that aliens could have been receiving them. tv programs are broadcast at a frequency of about 100mhz with about 100kw of total power in 30frames per second, which emanatesroughly uniformly in all directions. assume that interstellar space transmits these broadcasts without attenuation. no matter how smart they are, aliens would require at least one photon per frame to interpret our signals. findthe number of photons per unit time per unit area reaching a receiver on a possible planet in the nearest star system, which is about 4 light-years away (a light-year is the distance light travels in a year). if aliens aimed a receiver or detector directly at earth, how big (in diameter) would it have to be to receive a photon per frame

Will give brainliest! which statement best describes the similarities between fundamental forces? electromagnetic and strong nuclear forces influence the interaction between charged particles within an atom. gravitational and magnetic forces are both types of charges that occur in nature. nuclear and magnetic forces are both related to mass and weight. strong nuclear force is most like electrical force because they are both related to distance.

Which of the following best describes internal energy? a. the difference between the kinetic and potential energies of the particles in a system b. the sum of the kinetic and potential energies of the particles in a system c. the sum of the kinetic and thermal energies of the particles in a system d. the difference between the kinetic and thermal energies of the particles in a system