Question Number 136136 by BHOOPENDRA last updated on 19/Mar/21
Answered by mr W last updated on 19/Mar/21
$${a}=\frac{{F}}{{m}}=\frac{\mathrm{150}}{\mathrm{10}}=\mathrm{15}\:{m}/{s}^{\mathrm{2}} \\ $$$${at}\:{t}=\mathrm{12}\:{s}: \\ $$$${v}={at}=\mathrm{15}×\mathrm{12}=\mathrm{180}\:{m}/{s} \\ $$$${s}=\frac{\mathrm{1}}{\mathrm{2}}{at}^{\mathrm{2}} =\frac{\mathrm{1}}{\mathrm{2}}×\mathrm{15}×\mathrm{12}^{\mathrm{2}} =\mathrm{1080}\:{m} \\ $$$${W}={Fs}=\mathrm{150}×\mathrm{1080}=\mathrm{162}\:\mathrm{000}\:{J}=\mathrm{162}\:{kJ} \\ $$$${or}\:=\frac{\mathrm{1}}{\mathrm{2}}{mv}^{\mathrm{2}} =\frac{\mathrm{10}×\mathrm{180}^{\mathrm{2}} }{\mathrm{2}}=\mathrm{162}\:\mathrm{000}\:{J} \\ $$