Question

Make a program that (i) asks the user for a temperature in Fahrenheit degrees and reads the number; (ii) computes the correspodning temperature in Celsius degrees; and (iii) prints out the temperature in the Celsius scale. Name of program file: f2c_qa.py.

Short answer

Create `f2c_qa.py`, read Fahrenheit input, compute Celsius using \( C = \frac{5}{9} imes (F - 32) \), and print result.

Step-by-step solution

Understand the Formula

To convert temperatures from Fahrenheit to Celsius, use the formula: \[ C = \frac{5}{9} imes (F - 32) \]where \( C \) is the temperature in Celsius and \( F \) is the temperature in Fahrenheit.

Create the Program Structure

Start by creating a new Python file named `f2c_qa.py`. This file will contain all the code needed for your program. Begin by planning the three main tasks: asking for input, converting the temperature, and printing the result.

Write the Input Code

Inside `f2c_qa.py`, write a statement to ask the user for the temperature in Fahrenheit. Use the `input()` function to read this input from the user, and convert it to a float. Example: ```python fahrenheit = float(input("Enter temperature in Fahrenheit: ")) ```

Convert Fahrenheit to Celsius

Now, using the formula from Step 1, calculate the Celsius temperature based on the input Fahrenheit value. Example: ```python celsius = (5/9) * (fahrenheit - 32) ```

Print the Celsius Temperature

Finally, use the `print()` function to output the temperature in Celsius to the user. You should format the message so that it clearly communicates the result. Example: ```python print("Temperature in Celsius: ", celsius) ```

Test the Program

Save the file and run your program to ensure it correctly asks for the input, computes the conversion, and prints the correct results. Try various input values to verify accuracy.

Key concepts

Fahrenheit to Celsius Conversion

Converting temperatures between Fahrenheit and Celsius is a common task in both math and programming. The formula to convert Fahrenheit (F) to Celsius (C) is:\[ C = \frac{5}{9} \times (F - 32) \] This formula expresses the temperature in Celsius by taking the difference between the Fahrenheit temperature and 32, then multiplying the result by 5/9. The number 32 is the zero point of the Fahrenheit scale since water freezes at 32°F, and multiplying by 5/9 accounts for the difference in scale between Celsius and Fahrenheit.
If you start with Fahrenheit values, just subtract 32 and scale down by multiplying with 5/9 to get the corresponding Celsius temperature. This is crucial for correctly interpreting temperatures in other countries, as many prefer the Celsius scale.

User Input Handling in Python

User input is essential in making interactive programs. In Python, the `input()` function allows us to capture data directly from users. For conversion programs, we need to be sure the user's input is captured correctly.
This function reads user input as a string, so we need to convert the input into a numerical type when performing mathematical operations. For temperature conversions, changing the input to a float is common.
Here's a simple line of code:

• `fahrenheit = float(input("Enter temperature in Fahrenheit: "))`

Using `float()` ensures the number can have decimals, adding precision to calculations. Remember, without conversion, attempting math operations on a string will lead to errors.

Mathematical Operations in Python

Programming languages like Python excel at handling numbers and performing complex calculations. For converting Fahrenheit to Celsius, the main operation involves arithmetic calculations – subtracting, multiplying, and handling floating-point division.
Python defines the `*` operator for multiplication and `/` for division, which are crucial in applying the conversion formula. Python by default handles floating-point division accurately, ensuring our temperature conversion results are precise.
For example, to convert a Fahrenheit input to Celsius, the code snippet is:

• `celsius = (5/9) * (fahrenheit - 32)`

This simple operation demonstrates how easily Python handles arithmetic, letting us focus on the logic and flow of the program without worrying about basic math rules.