171- A container holds $1000$ g of water and $200$ g of ice at zero degrees Celsius. In thermal equilibrium, a piece of special metal is heated to $400\,\dfrac{\text{J}}{\text{kg}\cdot\text{K}}$ and placed inside the container at $250$ degrees Celsius. At minimum, how many grams of metal must be placed so that some ice remains in the container? $$\left( L_f = 336000\,\frac{\text{J}}{\text{kg}},\quad c_{\text{water}} = 4200\,\frac{\text{J}}{\text{kg}\cdot\text{K}} \text{ and heat loss is negligible.} \right)$$ $375$ (1) $672$ (2) $860$ (3) $950$ (4) \begin{flushright} Calculation Space \end{flushright} %% Page 13 Physics 120-A Page 12
\textbf{171-} A container holds $1000$ g of water and $200$ g of ice at zero degrees Celsius. In thermal equilibrium, a piece of special metal is heated to $400\,\dfrac{\text{J}}{\text{kg}\cdot\text{K}}$ and placed inside the container at $250$ degrees Celsius. At minimum, how many grams of metal must be placed so that some ice remains in the container?
$$\left( L_f = 336000\,\frac{\text{J}}{\text{kg}},\quad c_{\text{water}} = 4200\,\frac{\text{J}}{\text{kg}\cdot\text{K}} \text{ and heat loss is negligible.} \right)$$
\hfill $375$ (1) \hfill $672$ (2) \hfill $860$ (3) \hfill $950$ (4) \hfill
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\textbf{Calculation Space}
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