The area of a rectangular loop of wire is 3.6 ×10-3 m2. the loop is placed in amagnetic field that changes from 0.20 t to 1.4 t in 1.6 s. theplane of the loop is perpendicular to the direction of the magneticfield. what is the magnitude of the induced emf in thatloop?
a constant magnetic field of 0.50 t is applied to a rectangularloop of area 3.0 × 10-3 m2. if thearea of this loop changes from its original value to a new value of1.6 × 10-3 m2 in 1.6 s, whatis the emf induced in the loop?

if the number ofturns in a rectangular coil of wire that is rotating in a magneticfield is doubled, what happens to the induced emf, assuming all theother variables remain the same?

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