On a temperature scale '$\mathrm{X}$', the boiling point of water is $65^{\circ} \mathrm{X}$ and the freezing point is $-15^{\circ} \mathrm{X}$. Assume that the $\mathrm{X}$ scale is linear. The equivalent temperature corresponding to $-95^{\circ} \mathrm{X}$ on the Farenheit scale would be:
Solution
We are given two temperature scales: the X-scale and the Celsius scale. The relationship between two linear temperature scales can be expressed as follows:
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$$\frac{X - X_{\text{freeze}}}{X_{\text{boil}} - X_{\text{freeze}}} = \frac{C - C_{\text{freeze}}}{C_{\text{boil}} - C_{\text{freeze}}}$$
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Here, $X_{\text{freeze}}$ and $X_{\text{boil}}$ are the freezing and boiling points of water on the X-scale, while $C_{\text{freeze}}$ and $C_{\text{boil}}$ are the freezing and boiling points of water on the Celsius scale.
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We are given the following values:
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X-scale:<br/><br/>
$X_{\text{boil}} = 65^{\circ} \mathrm{X}$<br/><br/>
$X_{\text{freeze}} = -15^{\circ} \mathrm{X}$
<br/><br/>
Celsius scale:<br/><br/>
$C_{\text{boil}} = 100^{\circ} \mathrm{C}$<br/><br/>
$C_{\text{freeze}} = 0^{\circ} \mathrm{C}$
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Our goal is to find the equivalent temperature of $-95^{\circ} \mathrm{X}$ on the Fahrenheit scale.
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Step 1: Convert $-95^{\circ} \mathrm{X}$ to Celsius:
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Use the relationship between X-scale and Celsius scale:
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$\frac{-95 - (-15)}{65 - (-15)} = \frac{C - 0}{100 - 0}$
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Simplify and solve for C:
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$\frac{-80}{80} = \frac{C}{100}$
$C = -100^{\circ} \mathrm{C}$
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Step 2: Convert $-100^{\circ} \mathrm{C}$ to Fahrenheit:
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Use the conversion formula between Celsius and Fahrenheit:
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$T_F = \frac{9}{5}T_C + 32$
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Substitute the Celsius temperature:
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$T_F = \frac{9}{5} \times (-100) + 32$<br/><br/>
$T_F = -180 + 32$<br/><br/>
$T_F = -148^{\circ} \mathrm{F}$
<br/><br/>
So, the equivalent temperature corresponding to $-95^{\circ} \mathrm{X}$ on the Fahrenheit scale is $-148^{\circ} \mathrm{F}$.
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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