Smugglers. Rumor has it that a company has been smuggling gold out of the country using sealed, cylindrical barrels with hollow walls. They pour molten gold into the hollows, and then fill the remainder of the barrel's internal volume with packing peanuts. The total mass of the gold-walled barrel was designed so that it exactly matches those used to transport a volatile chemical that cannot be exposed to air (and therefore the barrel cannot be opened and checked). The X-ray machine usually used to screen containers is suspiciously damaged and not available. (a) There are 20 barrels total, and they are all identical: mass m = 50.0 kg, height h = 1.2 m, and diameter D = 0.25 m. How do you determine which ones have walls filled with gold (and are essentially hollow on the interior except for packing peanuts) and those completely filled with the volatile chemical (a tightly-packed powder) where the mass is uniformly distributed? Hint: apply the concepts of moment of inertia. Is the moment of inertia of the hollow cylinder less than, greater than or equal to the moment of inertia of the solid cylinder? (b) Assume that, in the case of the gold-filled barrels, the entire mass is concentrated at the outer wall of the barrel and, in the case of the barrels filled with the chemical, the mass is distributed evenly throughout the volume of the cylinder. You can neglect the circular bottoms and the lids of the barrels, and assume there is no slipping. What is the acceleration of the center of mass of each of the barrels as they roll down a 30° inclined plane? (c) How much time does it take each barrel to roll 10.0 m down the 30° plane? (a) (b) hollow cylinder Number solid cylinder Number (c) hollow cylinder Number solid cylinder Number Units Units Units Units > <

Smugglers. Rumor has it that a company has been smuggling gold out of the country using sealed, cylindrical barrels with hollow walls. They pour molten gold into the hollows, and then fill the remainder of the barrel's internal volume with packing peanuts. The total mass of the gold-walled barrel was designed so that it exactly matches those used to transport a volatile chemical that cannot be exposed to air (and therefore the barrel cannot be opened and checked). The X-ray machine usually used to screen containers is suspiciously damaged and not available. TUL (a) There are 20 barrels total, and they are all identical: mass m = 50.0 kg, height h = 1.2 m, and diameter D = 0.25 m. How do you determine which ones have walls filled with gold (and are essentially hollow on the interior except for packing peanuts) and those completely filled with the volatile chemical (a tightly-packed powder) where the mass is uniformly distributed? Hint: apply the concepts of moment of inertia. Is the…

Disintegration. NUCLEAR PHYSICS. Explain what it's being used. It has been found that a sample of uranium oxide (U308), freshly prepared from an ore of uranium, emits 20.5 a particles per mg per second. If we have A238 = 4.8 × 10¬185-1, is it possible to have a 1mg sample?

1) Determine the change in chemical energy each second required to produce this increase in electric potential energy.   2) If there are roughly 7×10^11 of these cells in the body, how much chemical energy is used in pumping sodium ions each second?   3) Estimate the fraction of a person's metabolic rate used to pump these ions. Assume the metabolic rate to be 100 W.