Aflat-plate x-ray diffraction pattern was cuka radiation. it consisted of a series of spots arranged along a horizontal line containing the central spot and first-order layer lines above and below the central line. it was found that with a specimen-to-film distance of 30 mm the first order lines were 22.9 mm above and below the central spot. (a) calculate the spacing of the chain repeat c of the polymer crystals. (b) explain why only first-order layer lines are observed for this polymer and suggest how higher order lines may be obtained. (c) determine the angle through which the specimen would have to be tilted in order to obtain the (001) reflection on the diffraction pattern.

250✖️100 to get you answer

Texas-flood watch and coastal flood barrierscalifornia-try and look for under ground water stream 

Two 10¢  coins  (dimes)  carrying identical charges  are  lying 2.5 m apart  on a  table.  if each  of  these coins experiences  an  electrostatic force  of  magnitude 2.0 n due  to the  other coin.  the charge on each coin is :     52.2 uc

Stars are born within the clouds of dust and scattered throughout most galaxies. a familiar example of such as a dust cloud is the orion nebula. turbulence deep within these clouds gives rise to knots with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction. as the cloud collapses, the material at the center begins to heat up. known as a protostar, it is this hot core at the heart of the collapsing cloud that will one day become a star. three-dimensional computer models of star formation predict that the spinning clouds of collapsing gas and dust may break up into two or three blobs; this would explain why the majority the stars in the milky way are paired or in groups of multiple stars.therefor, i would say the answer is: dust and gases contract.i hope this ! < 3