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Expert-verified(a) On a winter day, a certain house loses 5.00×108 J of heat to the outside (about 500,000 Btu). What is the total change in entropy due to this heat transfer alone, assuming an average indoor temperature of 21.0 ºC and an average outdoor temperature of 5.00 ºC ? (b) This large change in entropy implies a large amount of energy has become unavailable to do work. Where do we find more energy when such energy is lost to us?
The total entropy change is 98000 J/K. More energy can be found by finding things that would keep the house and us warm.
The entropy represents the randomness of a thermodynamic system. It is the measure of disorder in a system.
Heat transferred is 5×108J
Temperature indoor Th = 21 ̊ C = 294 K
Temperature outdoor Tc = 5 ̊ C = 278K
Change in entropy ∆S = uncaught exception: Http Error #403in file: /var/www/html/integration/lib/com/wiris/plugin/impl/HttpImpl.class.php line 68#0 /var/www/html/integration/lib/php/Boot.class.php(769): com_wiris_plugin_impl_HttpImpl_1(Object(com_wiris_plugin_impl_HttpImpl), NULL, 'http://www.wiri...', 'Http Error #403') #1 /var/www/html/integration/lib/haxe/Http.class.php(532): _hx_lambda->execute('Http Error #403') #2 /var/www/html/integration/lib/php/Boot.class.php(769): haxe_Http_5(true, Object(com_wiris_plugin_impl_HttpImpl), Object(com_wiris_plugin_impl_HttpImpl), Array, Object(haxe_io_BytesOutput), true, 'Http Error #403') #3 /var/www/html/integration/lib/com/wiris/plugin/impl/HttpImpl.class.php(30): _hx_lambda->execute('Http Error #403') #4 /var/www/html/integration/lib/haxe/Http.class.php(444): com_wiris_plugin_impl_HttpImpl->onError('Http Error #403') #5 /var/www/html/integration/lib/haxe/Http.class.php(458): haxe_Http->customRequest(true, Object(haxe_io_BytesOutput), Object(sys_net_Socket), NULL) #6 /var/www/html/integration/lib/com/wiris/plugin/impl/HttpImpl.class.php(43): haxe_Http->request(true) #7 /var/www/html/integration/lib/com/wiris/plugin/impl/RenderImpl.class.php(268): com_wiris_plugin_impl_HttpImpl->request(true) #8 /var/www/html/integration/lib/com/wiris/plugin/impl/RenderImpl.class.php(307): com_wiris_plugin_impl_RenderImpl->showImage('5461d5f4548c31b...', NULL, Object(PhpParamsProvider)) #9 /var/www/html/integration/createimage.php(17): com_wiris_plugin_impl_RenderImpl->createImage('
Here,
\[\Delta S\]- change in entropy.
Q - heat transferred.
T- temperature.
Change in indoor entropy
∆ Sh = - Q/Th
Change in outdoor entropy
∆Sc = Q/Tc
Total change in entropy
\begin{aligned} \Delta {S_{total}} = \Delta {S_h} + \Delta {S_c}\\ = - Q/{T_h} + Q/{T_c}\\= Q\left( {\frac{{ - 1}}{{294\;{\rm{K}}}} + \frac{1}{{278\;{\rm{K}}}}} \right)\\= 98000\;{\rm{J/K}}\end{aligned}
Therefore, the total change in entropy is 98000 J/K. More energy can be found by finding things that would keep the house and us warm like a heater, fire, woolen clothes, etc. We just need things that would provide us energy or keep energy trapped to perform work
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