Question Number 81124 by TawaTawa last updated on 09/Feb/20
Answered by Rio Michael last updated on 10/Feb/20
$$\left.\mathrm{b}\right)\:\left(\mathrm{i}\right)\:\mathrm{Energy}\:\mathrm{output}\:=\:\mathrm{work}\:\mathrm{done}\:\mathrm{in}\: \\ $$$$\mathrm{lifting}\:\mathrm{cement}\:\mathrm{to}\:\mathrm{the}\:\mathrm{height}\:\mathrm{B}\:=\:{mgsin}\theta×\mathrm{5} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\:\mathrm{50}{sin}\mathrm{60}×\mathrm{5}\:=\:\mathrm{216}.\mathrm{5}{J} \\ $$$$\left.\mathrm{ii}\right)\:\mathrm{Energy}\:\mathrm{input}\:=\:{Fd}\:=\:\mathrm{500}\:×\:\mathrm{5}\:=\:\mathrm{2500}{J} \\ $$$$\left(\mathrm{iii}\right)\:\mathrm{Efficiency}\:=\:\frac{\mathrm{work}\:\mathrm{output}}{\mathrm{work}\:\mathrm{inpu}}\:×\:\mathrm{100\%} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\:\frac{\mathrm{216}.\mathrm{5}}{\mathrm{2500}}\:×\:\mathrm{100}\:=\:\mathrm{8}.\mathrm{66\%} \\ $$$$\left.\mathrm{iv}\right)\:\mathrm{potential}\:\mathrm{energy}\:\mathrm{is}\:\mathrm{converted}\:\mathrm{to}\:\mathrm{kinetic}\:\mathrm{energy} \\ $$$$\mathrm{which}\:\mathrm{is}\:\mathrm{converted}\:\mathrm{to}\:\mathrm{sound}\:\mathrm{and}\:\mathrm{heat}\:\mathrm{energy}. \\ $$
Commented by TawaTawa last updated on 10/Feb/20
$$\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir} \\ $$