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Nata [24]
3 years ago
10

¿Juan quiere calentar una barra de aluminio de 100 g, para realizar un trabajo. La temperatura ambiente es de 27°C pero necesita

elevar la temperatura de la barra hasta los 60°C. Si el aluminio tiene un calor especifico de 0,215 cal/g°C que cantidad de calor necesita aplicar ?
Physics
1 answer:
Luda [366]3 years ago
8 0

Answer:

<em>709.5 cal</em>

<em></em>

Explanation:

masa m de la barra de aluminio = 100 g

temperatura ambiente = 27 ° C

<em>Asumiremos que la barra de aluminio está en equilibrio térmico con el ambiente. </em>

Esto significa que la temperatura inicial de la barra es de 27 ° C

temperatura final a la que la barra debe calentarse = 60 ° C

el aumento de temperatura ΔT será

ΔT = 60 ° C - 27 ° C = 33 ° C

capacidad calorífica específica c del aluminio = 0.215 cal/g°C

Calor C requerido = mcΔT

<em>C = 100 x 0.215 x 33 = 709.5 cal</em>

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Hence,the rate of entropy generation in the heat exchanger. is 0.1483Btu/s.R

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