Consider a piston-cylinder assembly in which air expands adiabatically from an initial state where pi= 100 lbf/in, u = 3.704 f/ib, and t = 1000°r, to a final state where p2 30 lb/in". the process is polytronic with n=1.4. the change in specific internal energy (in turib), can be expressed in terms of temperature change as au - (0.171)(12 - 11). determine the final temperature in "r). neglect kinetic and potential energy effects.

laticia draws the diagram below to show earth’s magnetic field.

answer

the arrows to the right of earth should point up.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.