Uncertainty in Newton's law of cooling

In summary, the conversation is discussing the uncertainty in Newton's law of cooling, specifically in the value of k. The relevant equations are also mentioned. The uncertainty is calculated using a root-sum-square approach and the question of finding uncertainty involving logs is raised.
  • #1
sunmoonlight
8
1
Homework Statement
Uncertainty in Newton's law of cooling
Relevant Equations
T(t) = = 𝑇_𝐴+(𝑇_𝑜−𝑇_𝐴)𝑒^(−𝑘𝑡)
I'm finding the uncertainty of k, given that each temperature has an uncertainty of +/- 0.5 degress.
 
Physics news on Phys.org
  • #2
sunmoonlight said:
Homework Statement: Uncertainty in Newton's law of cooling
Relevant Equations: T(t) = = 𝑇_𝐴+(𝑇_𝑜−𝑇_𝐴)𝑒^(−𝑘𝑡)

I'm finding the uncertainty of k, given that each temperature has an uncertainty of +/- 0.5 degress.
You will also need approximate values for the temperatures.
Per forum rules, please show some attempt.
 
  • #3
say the T(O) = 90 +/- 0.5, T(t): 60 +/- 0.5, TA = 10 +/- 0.5, temp difference (T(t) - TA) is 50 degrees +/- 0.5, t= 100s
1. Is the uncertainty for ln (T(t) - TA) = 1/2*(ln50.5 - ln49.5) = +/-0.01?
2. If you substitute the values into the eqt, you get k = (ln50/80)/-100, so what's the uncertainty for k (like how do you find uncertainty involving logs?)
 
  • #4
sunmoonlight said:
say the T(O) = 90 +/- 0.5, T(t): 60 +/- 0.5, TA = 10 +/- 0.5, temp difference (T(t) - TA) is 50 degrees +/- 0.5, t= 100s
1. Is the uncertainty for ln (T(t) - TA) = 1/2*(ln50.5 - ln49.5) = +/-0.01?
2. If you substitute the values into the eqt, you get k = (ln50/80)/-100, so what's the uncertainty for k (like how do you find uncertainty involving logs?)
There are different concepts of uncertainty. An engineer worried about engineering tolerances would just look at the combinations of the extreme values. A scientist would take the given uncertainties as standard deviations in normal distributions and use root-sum-square approaches to combine them. I assume you are looking for the latter.

Can you find the uncertainty in ##e^{-kt}##?
 

1. What is Newton's law of cooling?

Newton's law of cooling is a mathematical equation that describes the rate at which an object cools down in a surrounding environment. It states that the rate of change of temperature of an object is directly proportional to the difference between its temperature and the temperature of its surroundings.

2. What is the role of uncertainty in Newton's law of cooling?

Uncertainty in Newton's law of cooling refers to the potential error or inaccuracy in the measurements or calculations used to determine the rate of cooling. This can be caused by various factors such as measurement limitations, experimental errors, and environmental fluctuations.

3. How is uncertainty calculated in Newton's law of cooling?

Uncertainty in Newton's law of cooling can be calculated using various statistical methods such as standard deviation, confidence intervals, and error propagation. These methods take into account the variability and potential sources of error in the measurements and calculations to determine a range of possible values for the uncertainty.

4. How does uncertainty impact the validity of Newton's law of cooling?

The presence of uncertainty in measurements and calculations can affect the accuracy and precision of the results obtained from Newton's law of cooling. A high level of uncertainty can indicate that the data is not reliable and may need to be reevaluated or improved upon to increase the validity of the law.

5. How can uncertainty in Newton's law of cooling be minimized?

To minimize uncertainty in Newton's law of cooling, it is important to carefully control and monitor the experimental conditions, use accurate and precise measurement equipment, and perform multiple trials to reduce random errors. Additionally, using more advanced statistical techniques and considering potential sources of systematic error can also help to minimize uncertainty.

Similar threads

  • Introductory Physics Homework Help
Replies
4
Views
256
  • Introductory Physics Homework Help
Replies
3
Views
729
  • Introductory Physics Homework Help
Replies
8
Views
816
  • Introductory Physics Homework Help
Replies
15
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
877
  • Introductory Physics Homework Help
Replies
9
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
3K
  • Introductory Physics Homework Help
Replies
1
Views
2K
Replies
6
Views
2K
Back
Top