Table A: Effect of Height on Temperature [tex]$\left( T_{i} = 25^{\circ}C; m_{w} = 1.0 \, \text{kg}; m_{c} = 5.0 \, \text{kg} \right.$[/tex] )

\begin{tabular}{|c|c|c|c|c|}
\hline
\begin{tabular}{l}
h \\
(m)
\end{tabular} & \begin{tabular}{l}
[tex]$T_{f}$[/tex] \\
[tex]$\left({ }^{\circ}C \right)$[/tex]
\end{tabular} & \begin{tabular}{l}
[tex]$\Delta T$[/tex] \\
[tex]$\left({ }^{\circ}C \right)$[/tex]
\end{tabular} & \begin{tabular}{l}
[tex]$PE_{g}$[/tex] \\
(kJ)
\end{tabular} & \begin{tabular}{l}
[tex]$\Delta H$[/tex] \\
(kJ)
\end{tabular} \\
\hline
100 & 26.17 & 1.17 & & \\
\hline
200 & 27.34 & 2.34 & & \\
\hline
500 & 30.86 & 5.86 & & \\
\hline
1000 & 36.72 & 11.72 & & \\
\hline
\end{tabular}

Use the data provided to calculate the amount of energy generated for each cylinder height. Round your answers to the nearest tenth.

[tex]$100 \, \text{m}:$[/tex] [tex]$\square$[/tex] kJ

[tex]$200 \, \text{m}:$[/tex] [tex]$\square$[/tex] kJ

[tex]$1000 \, \text{m}:$[/tex] [tex]$\square$[/tex] kJ



Answer :

To determine the amount of heat generated ([tex]\(\Delta H\)[/tex]) for each cylinder height using the provided data, follow these steps:

1. Given Data:
- Initial temperature, [tex]\(T_i = 25^\circ \text{C}\)[/tex]
- Mass of water, [tex]\(m_w = 1.0 \text{kg}\)[/tex]
- Mass of cylinder, [tex]\(m_c = 5.0 \text{kg}\)[/tex]
- Specific heat capacity of water, [tex]\(c_w = 4.18 \text{ J/(g°C)} = 4.18 \times 10^{-3} \text{ kJ/(kg°C)}\)[/tex]

2. Data from the Table:
- Heights ([tex]\( h \)[/tex]): 100 m, 200 m, 500 m, 1000 m
- Final temperatures ([tex]\( T_f \)[/tex]): 26.17°C, 27.34°C, 30.86°C, 36.72°C
- Change in temperature ([tex]\( \Delta T \)[/tex]): 1.17°C, 2.34°C, 5.86°C, 11.72°C

3. Formula for Change in Enthalpy ([tex]\( \Delta H \)[/tex]):
[tex]\[ \Delta H = m_w \times c_w \times \Delta T \][/tex]
Here, [tex]\( m_w \)[/tex] is the mass of water (in kg), [tex]\( c_w \)[/tex] is the specific heat capacity of water (in kJ/(kg°C)), and [tex]\( \Delta T \)[/tex] is the change in temperature (in °C).

4. Calculations:

- For 100 m:
[tex]\[ \Delta H_{100} = 1.0 \, \text{kg} \times 4.18 \times 10^{-3} \, \text{kJ/(kg°C)} \times 1.17 \, \text{°C} \][/tex]
[tex]\[ \Delta H_{100} = 0.0048906 \, \text{kJ} \][/tex]

- For 200 m:
[tex]\[ \Delta H_{200} = 1.0 \, \text{kg} \times 4.18 \times 10^{-3} \, \text{kJ/(kg°C)} \times 2.34 \, \text{°C} \][/tex]
[tex]\[ \Delta H_{200} = 0.0097812 \, \text{kJ} \][/tex]

- For 500 m:
[tex]\[ \Delta H_{500} = 1.0 \, \text{kg} \times 4.18 \times 10^{-3} \, \text{kJ/(kg°C)} \times 5.86 \, \text{°C} \][/tex]
[tex]\[ \Delta H_{500} = 0.0244948 \, \text{kJ} \][/tex]

- For 1000 m:
[tex]\[ \Delta H_{1000} = 1.0 \, \text{kg} \times 4.18 \times 10^{-3} \, \text{kJ/(kg°C)} \times 11.72 \, \text{°C} \][/tex]
[tex]\[ \Delta H_{1000} = 0.0489896 \, \text{kJ} \][/tex]

5. Rounding to the Nearest Tenth:
- [tex]\(\Delta H_{100} \approx 0.0 \, \text{kJ}\)[/tex]
- [tex]\(\Delta H_{200} \approx 0.0 \, \text{kJ}\)[/tex]
- [tex]\(\Delta H_{500} \approx 0.0 \, \text{kJ}\)[/tex]
- [tex]\(\Delta H_{1000} \approx 0.0 \, \text{kJ}\)[/tex]

Thus, the calculations show very small values of generated heat when rounded to the nearest tenth place:

- For 100 m: approximately [tex]\(0.0\)[/tex] kJ
- For 200 m: approximately [tex]\(0.0\)[/tex] kJ
- For 500 m: approximately [tex]\(0.0\)[/tex] kJ
- For 1000 m: approximately [tex]\(0.0\)[/tex] kJ