The girlfriend of a phs1282 student proposes to him and offers him a "golden" ring in the process. however, his girlfriend is a student in the department of accountancy and finance, and would struggle to afford a gold ring. additionally she is known to have a slightly dodgy character. after initially being flattered by the marriage proposal he therefore gets suspicious about whether the ring is actually made of gold. he therefore bring the ring to the phs「282 lab and measure its mass to be 2.80± 0.02 g and its volume to be 0.16 ± 0.03 cm3 . gold has a mass density of 19.3 g/cm3. could the ring be made of gold? (explain your answer) . brass has a mass density of 8.4 g/cm3 to 8.7 g/cm3 (depending on the composition of the alloy). could the ring be made of brass?

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light