# Help figuring out units in a power fit.

• charlies1902
In summary, the equation of interest is A=B*V^n, where A has units of W/(m^2*K), V has units of m/s, and B and n are parameters to be determined. When fitting a power trendline, B and n should have units of W/[m^2*K*(m/s)^n], with n being the value determined from the trendline.
charlies1902
The equation of interest is:
A=B*V^n

where A has units of W/(m^2*K)
W=watt, K=kelvin, m=meter
V has units of m/s.

B and n are parameters to be determined.I have a set of values that I put into excel to generate a plot. From the plot, I fit a power trendline to it and got the equation to be
A=20x^3Should B and n have units?

charlies1902 said:
The equation of interest is:
A=B*V^n

where A has units of W/(m^2*K)
W=watt, K=kelvin, m=meter
V has units of m/s.

B and n are parameters to be determined.

I have a set of values that I put into excel to generate a plot. From the plot, I fit a power trendline to it and got the equation to be
A=20x^3

Should B and n have units?

n doesn't have units. It's just 3. But A, B and x should definitely have units. You already know the units for A and x. You just need to find the units for B.

Dick said:
n doesn't have units. It's just 3. But A, B and x should definitely have units. You already know the units for A and x. You just need to find the units for B.

it should be (for C):
W/[m^2 * K * (m/s)^3]
where n=3
correct?

charlies1902 said:
it should be (for C):
W/[m^2 * K * (m/s)^3]
where n=3
correct?

If you mean the units for B, yes!

Dick said:
If you mean the units for B, yes!

Yeah, oops, thanks.

## 1. How do I calculate units in a power fit?

To calculate units in a power fit, you will need to use the equation y = ax^b, where y is the dependent variable, x is the independent variable, a is the coefficient, and b is the power. The units of the coefficient a will be the same as the units of y, while the units of x^b will depend on the value of b.

## 2. What is the significance of units in a power fit?

Units in a power fit are important because they represent the physical quantity being measured and help to determine the relationship between the variables. They also allow for the correct interpretation and comparison of data.

## 3. How do I ensure that my units are consistent in a power fit?

To ensure consistent units in a power fit, it is important to double-check the units of all variables and coefficients used in the equation. If necessary, convert units to a common system before performing the fit.

## 4. Can I use different units in a power fit?

It is not recommended to use different units in a power fit, as this can lead to incorrect results and interpretation. It is best to use consistent units throughout the entire fitting process.

## 5. What if my dependent and independent variables have different units?

If your dependent and independent variables have different units, you will need to use a unitless ratio or convert one of the variables to match the units of the other. This will ensure that the resulting units in the power fit are consistent.

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