Both pulleys are fixed to the shaft and as the shaft turns with constant angular velocity, the power of pulley a is transmitted to pulley b. the bearings are in proper alignment and exerted only force reactions on the shaft. note the positive direction of each axis.

a. determine the horizontal tension(t) in the belt on the pulley b if theta=0
b. determine the x, y,z components of the reaction at the journal bearing c(cx, cy, cz)
c. determine the x, y,z components of the reaction at the thrust bearing d(dx, dy, dz)

A50.0-n box is sliding on a rough horizontal floor, and the only horizontal force acting on it is friction. you observe that at one instant the box is sliding to the right at and that it stops in 2.25 s with uniform acceleration. what magnitude force does friction exert on this box

1400 kg car has a speed of 27 m/s. if it takes 7 s to stop the car, what is the impulse and the average force acting on the car?

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