A 86.7 N sack of grain is hoisted to a storage room 44 m above the ground ?oor of a grain elevator. How much How much work was required?Answer in units of JWhat is the potential energy of the sack ofgrain at this height?Answer in units of JThe rope being used to lift the sack of grainbreaks just as the sack reaches the storageroom.What kinetic energy does the sack have justbefore it strikes the ground ?oor?Answer in units of J
How much work was required W = F * d = 86.7 * 44 = 3814.8 J potential energy of the sack PE = m g h mg = 86.7 N PE = 86.37 * 44 = 3814.8 J kinetic energy e = 1/2 g * t^2 ----t^2 = 2 e / g = 2* 44 / 9.8 = 8.97959 -- t = 2.99659 s v = g * t = 9.8 * 2.99659= 29.366 m/s m = 86.7 / 9.8 = 8.847 kg KE = 1/2 m * v^2 = 0.5 * 8.847 * 29.336^2 = 3814.8 J Goodbye
