Finding the slope and intercept of a graph

In summary, the conversation discusses using the formula A = Bt / (3d2) to plot ln(A) vs. ln(3d2) for a given experiment. The slope and intercept of this graph represent ln(Bt) and -1, respectively, when the equation is rewritten in terms of x = ln(3d2) and y = ln(A).
  • #1
jumbogala
423
4

Homework Statement


I am given the formula A = Bt / (3d2)

d is what we changed, A is what was measured.

I had to plot ln(A) vs ln(3d2).

What do the slope and intercept of this graph represent?

Homework Equations





The Attempt at a Solution


ln (A) = ln (Bt / 3d2) = ln(Bt) - ln(3d2)

ln (A) / ln (3d2) = ln (Bt)/ln(3d2) - 1

After this I get stuck. Help please!
 
Physics news on Phys.org
  • #2
jumbogala said:

The Attempt at a Solution


ln (A) = ln (Bt / 3d2) = ln(Bt) - ln(3d2)

ln (A) / ln (3d2) = ln (Bt)/ln(3d2) - 1

After this I get stuck. Help please!

If you are plotting ln(A) vs. ln(3d2), then let

x = ln(3d2)
y = ln(A)​

and you are now plotting y vs. x.

Write your equation,

ln (A) = ln(Bt) - ln(3d2),​

in terms of x and y. The slope and intercept should become easier to identify.
 
  • #3


The slope and intercept of a graph represent important characteristics of the relationship between the variables being plotted. In this case, the graph is plotting ln(A) against ln(3d2), which suggests that there is a logarithmic relationship between A and 3d2. The slope of the graph represents the rate of change between ln(A) and ln(3d2), or the change in ln(A) for every unit change in ln(3d2). This can also be interpreted as the power to which 3d2 needs to be raised to get A. The intercept of the graph represents the value of ln(A) when ln(3d2) is equal to 0, or when d is equal to 0. This can also be interpreted as the initial value of A when d is equal to 0. In summary, the slope and intercept of the graph provide important information about the relationship between A and d, and can be used to make predictions and draw conclusions about the data.
 

FAQ: Finding the slope and intercept of a graph

What is the slope of a line on a graph?

The slope of a line on a graph is a measure of its steepness. It is calculated by dividing the change in the y-values (vertical change) by the change in the x-values (horizontal change). This is often written as "rise over run" or as the ratio of the change in y to the change in x.

How do I find the slope of a line on a graph?

To find the slope of a line on a graph, choose two points on the line and calculate the change in y and change in x between those two points. Then, divide the change in y by the change in x to find the slope. Alternatively, you can use the slope formula: m = (y2 - y1) / (x2 - x1), where (x1,y1) and (x2,y2) are the coordinates of two points on the line.

What does the slope of a line represent?

The slope of a line represents the rate of change or the steepness of the line. A positive slope indicates that the line is increasing, while a negative slope indicates that the line is decreasing. The larger the absolute value of the slope, the steeper the line is.

What is the y-intercept of a line on a graph?

The y-intercept of a line on a graph is the point where the line crosses the y-axis. It is the value of y when x is equal to 0. In other words, it is the value of y when the line intersects with the vertical axis of the graph. The y-intercept is often denoted as "b" in the slope-intercept form of a line: y = mx + b.

How do I find the y-intercept of a line on a graph?

To find the y-intercept of a line on a graph, locate the point where the line crosses the y-axis. This is the value of y when x is equal to 0. Alternatively, you can use the slope-intercept form of a line (y = mx + b) and identify the value of b, which is the y-intercept.

Back
Top