Respostas

2014-07-09T17:46:14-03:00
No bloco A:

Fr = m . a
T - P . sen = m . a
T - m . g . 0,5 = a
T - 5 = a
T = a + 5
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No bloco B:

Fr = m . a
P - T = m . a
m . g - T = m . a
20 - T = 2a
-T = 2a - 20
T = -2a + 20

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a + 5 = -2a + 20
a + 2a = 20 - 5
3a = 15
a = 5 m/s²
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T = a + 5
T = 10 N