If the specific heat of glass is .196, how many BTUs are needed to raise the temperature of 10 pounds of glass from 50° F to 70° F?

If the specific heat of glass is .196, how many BTUs are needed to raise the temperature of 10 pounds of glass from 50° F to 70° F?

• A. 40.2
• B. 39.2
• C. 59.2
• D. 36.2

Answer: (B)

To determine the number of BTUs needed to raise the temperature of a substance, you can use the specific heat formula: \[ \text{BTUs} = \text{Weight} \times \text{Specific Heat} \times \Delta T \] Where: - Weight is in pounds, - Specific Heat is in BTUs per pound per degree Fahrenheit, - \(\Delta T\) (change in temperature) is the final temperature minus the initial temperature in degrees Fahrenheit. In this scenario: - The weight of the glass is 10 pounds. - The specific heat of glass is 0.196 BTU/lb°F. - The initial temperature is 50°F, and the final temperature is 70°F, so \(\Delta T\) is \(70°F - 50°F = 20°F\). Now, substituting the values into the formula: \[ \text{BTUs} = 10 \, \text{lbs} \times 0.196 \, \frac{\text{BTU}}{\text{lb°F}} \times 20°F \] Calculating this step by step: 1. Multiply the specific heat by the weight: \[

To determine the number of BTUs needed to raise the temperature of a substance, you can use the specific heat formula:

[

\text{BTUs} = \text{Weight} \times \text{Specific Heat} \times \Delta T

]

Where:

• Weight is in pounds,

• Specific Heat is in BTUs per pound per degree Fahrenheit,

• (\Delta T) (change in temperature) is the final temperature minus the initial temperature in degrees Fahrenheit.

In this scenario:

• The weight of the glass is 10 pounds.

• The specific heat of glass is 0.196 BTU/lb°F.

• The initial temperature is 50°F, and the final temperature is 70°F, so (\Delta T) is (70°F - 50°F = 20°F).

Now, substituting the values into the formula:

[

\text{BTUs} = 10 , \text{lbs} \times 0.196 , \frac{\text{BTU}}{\text{lb°F}} \times 20°F

]

Calculating this step by step:

1. Multiply the specific heat by the weight:

[