A radioactive source is placed 2.0 cm from a detector. The count rate decreases slightly if a sheet of paper is inserted between the source and the detector. It is reduced to the background radiation level if the sheet of paper is replaced by a 1.0 em thick sheet of aluminium. What form (s) of radiation does this source emit? A. Alpha radiation only B. Beta and gamma radiation C. Alpha and beta radiation D. Gamma radiation only 15.

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5.Match each type of radiation with its properties. 1.can penetrate paper but not a sheet of metal such as aluminum foil 2.can travel no more than a few centimeters in air and cannot penetrate a piece of paper or human skin 3.can penetrate many materials but not concrete or lead a. gamma radiation b. beta radiation c. alpha radiation

1. Find the radiation dose, in grays, for each of the following a. A 5.5-mSv fluoroscopic x-ray series, with a relative biological effectiveness of 1.  b.  45 mSv of skin exposure by an α emitter, with relative biological effectiveness of 20.  c. 148 mSv of β– and γ rays from the 40K in your body, both of which have a relative biological effectiveness of 1.  [please answer all parts to the question]

3. The following graph shows the amount of mg for a radioactive substance. a. Determine the initial quantity of the material. b. Determine the half-life for this substance. 200 180 160 140 120 100 80 60 40 20 c. Determine the percent decrease per hour. d. Determine how long it will take for only 25 mg of the substance to remain. 10 (12,50) 15 20 25 30 W 35 40

The isotope of Curium 242Cm has a half-life of 160 days and emits alpha particles with an energy 6.1MeV. What is the initial power emitted by a sample of 242Cm with a starting number of N0 = 1018 atoms? Select one: a. 2.7 W. b. 49 mW. c. 308 kW. d. 15.6 W.

3. What is the 'best' radiation detecting device that you should use in finding a lost radioactive source that both emits ß and y-radiation? Justify your answer.

The isotope N N has a half-life of 9.96 min. Determine the time interval (in min) required for the activity of a sample of this isotope to decrease to 39.0% of its original value. min Additional Materials O Reading

A farmer lifts his hay bales into the top loft of his barn by walking his horse forward with a constant velocity of 1 ft/s. Determine the velocity and acceleration of the hay bale when the horse is 10 ft away from the barn. 20 ft The velocity of the hay bale when the horse is 10 ft away from the barn is ft/s. The acceleration of the hay bale when the horse is 10 ft away from the barn is | ft/s2.

58. . Radiation treatment of prostate cancer. In many cases, BIO prostate cancer is treated by implanting 60 to 100 small seeds of radioactive material into the tumor. The energy released from the decays kills the tumor. One isotope that is used (there are others) is palladium (10°Pd), with a half-life of 17 days. If a typical grain contains 0.250 g of 10°Pd, (a) what is its initial activity rate in Bq, and (b) what is the rate 68 days later?