Physics, 23.10.2019 00:00 MayFlowers
Acord of negligible mass runs around two massless, frictionless pulleys. a canister with mass m = 20 kg hangs from one pulley. a constant force f is exerted on the free end of the cord. (a) what magnitude of f is required to lift the canister at constant speed? (b) to lift the canister by 2.0 cm, how far must you pull the free end of the cord? (c) what is the work done on the canister by the tension in the cords attached to the canister? how does this compare to the work you do in pulling down on the cord? (d) what is the work done by the weight of the canister? (e) what is the net work done on the canister? (f) explain why the pulley system offers a mechanical advantage. does it offer an advantage from the viewpoint of energy?
Answers: 1
Physics, 21.06.2019 18:30, iliketurtures
Three archers each fire four arrows at a target. joe’s four arrows hit at points 10 cm above, 10 cm below, 10 cm to the left, and 10 cm to the right of the center of the target. all four of moe’s arrows hit within 1 cm of a point 20 cm from the center, and flo’s four arrows hit within 1 cm of the center. the contest judge says that one of the archers is precise but not accurate, another archer is accurate but not precise, and the third archer is both accurate and precise. which description applies to which archer? explain
Answers: 2
Physics, 21.06.2019 23:00, hunterdylan01
Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?
Answers: 1
Acord of negligible mass runs around two massless, frictionless pulleys. a canister with mass m = 20...
English, 25.10.2019 19:43
Mathematics, 25.10.2019 19:43