Respostas

2014-03-12T19:09:08-03:00
Resposta

m = 800kg
V = 72 /3,6
V = 20m/s

Formula

Ec = m.V² /2

Ec = 800.20² /2

Ec = 800.400 /2

Ec = 320000/2

Ec = 160000J   ou    160kJ
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2014-03-12T19:09:23-03:00
E E d c = ∆ 2 202 2 dmv mv E = − ( )2800 202Ed⋅= − 51,6 10 E J
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