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Physical therapists know as you soak tired muscles in a hot tub, the water will cool down as you heat up. If a 67.9 kg person at 37.1 oC immerses in 50.2 kg of water at 40.5o C, the equilibrium temperature is 38.7 oC.

What is the specific heat of the person?
Use 4.186 kJ/kgoC for the specific heat of water.

User Aury
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1 Answer

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Answer:

c = 5032.8J/kg°C

Step-by-step explanation:

the transfer of heat is given by


Q_1=-Q_2\\\\Q=cm(T_f-T_i)

c is the specific heat, m the mass and T the temperatures at equilibrium an at the beginning.

By replacing we obtain


c_1m_1(T_f-T_(1i))=-c_2m_2(T_f-T_(2i))\\\\c_2=-(c_1m_1(T_f-T_(1i)))/(m_2(T_f-T_(2i)))=-((67.9kg)(4186J/kg\°C)(38.7\°C-37.1\°C))/((50.2kg)(38.7\°C-40.5\°C))\\\\c_2=5032.8(J)/(kg\°C)

hope this helps!!

User Krl
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