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(i) Work done = P.E gained ;
= mgh
= 500 x 4 x 10;
= 20,000J;
(ii) Power = work done
time taken
= 20,000/8
= 2.5KW ; or (2500 watts);
(iii) Efficiency = work output x100;
work input
= 2.5/2.8 x 100;
= 89.29%;
sharon kalunda answered the question on April 2, 2019 at 09:00
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