Radioactive iodine (radioiodine) is given to patients with some forms of thyroid cancer in order to destroy the cancer cells. 131I has a half-life of 8 days. Women who have been treated with 131I are advised to not become pregnant for 180 days (approximately 6 months) to avoid the radioactive contamination of a developing fetus. If a woman has been given a dose of 10 mCi (millicurie, a measurement of radiation), how much 131I will still be in her system when she can safely become pregnant?

A. 1.7 x 10-6 mCi
B. 22.5 x 10-6 mCi
C. There will be no iodine-131 left in her system after 180 days.
D. 3.125% of the original isotope

An artificial satellite circles the earth in a circular orbit at a location where the acceleration due to gravity is 6.03 m/s^2. determine the orbital period of the satellite.

Truck traveling west on the highway experiences an acceleration to the east. what could be the cause of this acceleration

Some material consisting of a collection of microscopic objects is kept at a high temperature. a photon detector capable of detecting photon energies from infrared through ultraviolet observes photons emitted with energies of 0.3 ev, 0.5 ev, 0.8 ev, 2.0ev, 2.5ev, and 2.8ev. these are the only photon energies observed. (a) draw and label a possible energy-level diagram for one of the microscopic objects, which has four bound states. on the diagram, indicate the transitions corresponding to the emitted photons. explain briefly. (b) would a spring–mass model be a good model for these microscopic objects? why or why not? (c) the material is now cooled down to a very low temperature, and the photon detector stops detecting photon emissions. next, a beam of light with a continuous range of energies from infrared through ultraviolet shines on the material, and the photon detector observes the beam of light after it passes through the material. what photon energies in this beam of light are observed to be significantly reduced in intensity (“dark absorption lines”)? explain briefly.