An accurate measurement of the fundamental spin-spin relaxation time (t2) comes from the amplitude of the "spin echo" as a function of delay time (t). the experiment involves a 900 pulse that rotates the spins into the x-y plane, where they precess at a range of frequencies due to the range of local fields. after the delay time t, a 180° pulse is applied so that the spins that were ahead by precessing faster are inverted to become behind the spins that precessed slower. a large-amplitude spin echo occurs at an additional delay of t, when the faster precessing spins temporarily coincide with the slower precessing spins. question 1 2 pts when the delay time between the 900 and 1800 pulses is t-5.66 ms, the spin echo (that occurs at a later time) becomes 1/e of its initial amplitude. the resulting spin-spin relaxation time is t2 d question 2 2 pts the table (pasted below) gives the amplitudes of the spin echo as a function of the delay time between 90° and 180° pulses. fitting the data to an exponential r delay(ms) 0.2 0.5 echolv) 4024 3.786 3.364 2.791 2.239 1.868 1.725 1.152 0.838 0.462 7.5 10 15 elaxation function yields a spin-spin relaxation time of ta ms

the answer is to check all of them! they all apply well at least i think so!

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

as we probably am aware that our atmosphere or air have various levels, each level has different gasses, and each gas has another porousness. at the point when the light originates from lower porousness to higher penetrability, it alters its course. with the goal that implies that when the light originates from the moon to the earth, it alters it's course a lot more occasions. it essentially implies that the state of the light piece of the moon is changed on the earth.

not copied too! hope this !

joke:

h o h o hope you have a merry christmas!