Question

numerical methods ( Chapra & Canale Chapter 17: Linear Regression)

Temperature(K)	Steam pressure (mmHg)
273	4,6
303	31,8
323	92,5
343	233,7
363	525,8

The vapor pressure of the water at different temperatures is given in the table below:

a) a. Draw a graph showing the change of vapor pressure with temperature (in Excel file)

b) write how a linear model can be adapted to this data.

c. Fit this data into a linear model.

D. Show actual values and your model on the same chart (in the same Excell file).

to. The difference between the calculated values from the model and the actual values is

Export in the column (in the same Excell file).

Answer 1

a)

b)

Here, the scatterplot shows that pressure and temperature have a linear relationship. Hence, a linear regression model can be applied here.

c)

We will be applying the Linear regression model here, it can be done by using the function LINEST(y_value, x_value, TRUE, TRUE) where y_values contain values of Steam pressure here and x_values have temperature values.

Select 5 rows and 2 columns and then write the formula in the first cell and after that, press Shift + Ctrl + Enter.    

The equation comes out to be -

Steam pressure = -15731.4 + 54.54*Temperature              

d)

Temperature	Steam Pressure	Predicted Steam pressure
273	46	-841.2459016
303	318	795.0327869
323	925	1885.885246
343	2337	2976.737705
363	5258	4067.590164