(UFLA-95)Uma barra de ferro homogênea é aquecida de 10ºC até 60ºC. Sabendo-se que a barra a 10ºC tem um comprimento igual a 5 m e que o coeficiente da dilatação
linear do ferro é igual 1,2 x 10-6
ºC-1
, podemos afirmar que a variação de dilatação
ocorrida e o comprimento final da barra foram de:
a)5×10-4m; 5,0005m
b)2×10-4m; 5,0002m
c)4×10-4m; 5,0004m
d)3×10-4m; 5,0003m
e)6×10-4m; 5,0006m

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