Evangelista torricelli was the first person to realize that we live at the bottom of an ocean of air. he correctly surmised that the pressure of our atmosphere is attributable to the weight of the air. the density of air at 0°c at the earth's surface is 1.29 kg/m3. the density decreases with increasing altitude (as the atmosphere thins). on the other hand, if we assume that the density is constant at 1.29 kg/m3 up to some altitude h, and zero above that altitude, then h would represent the depth of the ocean of air.

(a) use this model to determine the value of h that gives a pressure of 1.00 atm at the surface of the earth.

(b) would the peak of mt. everest rise above the surface of such an atmosphere?

yes or no?

Many machines- including inclined planes such as ramps- increase the strength of the force put into the machine but decrease the distance over which the force is applied. true or false

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

Aweight lifter raises a 1600 n barbell to a height of 2.0 meters. how much work was done? w = fd question 6 options: 3000 joules 30 joules 320 joules 3200 joules