Astudent’s backpack, full of textbooks, is hung from a spring scale attached to the ceiling of an elevator. when the elevator is accelerating downward at 23.8 m/s , the scale reads 60 n. (a) what is the mass of the backpack? (b) what does the scale read if the elevator moves upward while speeding up at a rate 23.8 m/s ? (c) what does the scale read if the elevator moves upward at constant velocity? (d) if the elevator had no brakes and the cable supporting it were to break loose so that the elevator could fall freely, what would the spring scale read? gold vs blue and black

You are a researcher for a golf club manufacturer. you are given two identical looking cubes of a metal alloy. you are informed that they are made of the exact same material, but one is crystalline, whereas the other is amorphous. it is your job to determine which one is amorphous this one is more stress-resistant and is useful in reinforcing golf clubs. which of the following is the best way to determine which is which? a. determine the density of each cube. the more dense one is the amorphous solid. b. melt both cubes and look for a broader range of melting temperatures. the one that melts over a broader range of temperatures is the amorphous solid. c. determine the density of each cube. the less dense cube is the amorphous solid. d. melt both cubes and measure the range of melting temperatures. the one that melts over a narrower range of temperatures is the amorphous solid.