Tuesday, February 12, 2008

Activity 4.3 Question

How do we know if a scientific theory is valid?

8 comments:

Zach Gates said...

We know if a scientific theory is valid if there is an experiment that has been proven to work and follows the laws of thermodynamics.

Christopher Noda said...

there are many way's to know if a scientific theory is valid or not. First of all one of the best ways to find out is if there is an experiment that was conducted by the person who thought of the theory. If someone is able to prove their theory then a lot more people will believe it. Another way to tell if a theory is true or not is to give an example. the more a person reading the theory can relate to it the more likely they are to believe it. This was why Gustave hirn's theory was proven to be more effective then joseph blacks theory. Gustave gave us a picture and a fully explained experiment to explain his ides while Black gave us a story with no proof. This is what might aid to the factor when someone is trying to support a throry. An experiment must also metion the loss of energy to the air because only in a perfect world will energy never be lost.

bmaples said...

We know if a scientific theory is valid by providing evidence and or an experiment to support the theory. That is why Hirn's theory called the Kinetic Theory was easier to be proven a theory because he had an experiment with the stone, lead, and iron which proved his theory.

Erin Holiday said...

To prove a scientific theory there must be evidence, even if that evidence may be indirect. For example, by the 1700s, most scientists agreed that all materials were made of atoms and that atoms were bonded together to create molecules. They agreed on this despite the fact that they had never seen an atom or molecule due to the lack of a strong enough microscope. Even so, atoms and molecules were accepted to exist because of indirect evidence from a variety of experiments that concluded atoms and molecules must exist. Another way a scientific theory may be proven valid is through experiments with multiple trials that have consistant results. For example Gustave Hirn did an experiment in which he allowed a huge iron pendulum to repeatedly swing into a small piece of lead, crushing it against a stone anvil. In doing this experiment he discovered that the battering of the stones caused the temperature of the lead to rise without causing a decrease in the temperature of the pendulum or the anvil. He then developed the Kinetic theory which states that all the atoms and molecules of a substance are in motion, and that the faster they move the higher the temperature of that substance is. Another way to prove a theory valid is to check it against the laws of thermodynamics and other accepted laws. For instance, the kinetic theory fit into the laws of thermodynamics because when two objects of different temperatures come into contact, the hotter object's faster moving atoms collide with the slow moving atoms of the cooler object. Heat is then transfered and the slower atoms move faster while the faster atoms slow down. These are some ways that a scientific theory can be proven valid.

anellore said...

We know if a scientific theory is valid by seeing if whoever made the theory had a experiment to prove his theory. Example: Joseph Black didn't test his theory(Caloric theory) so we don't know if it is true or not.

Suzie said...

To determine if a scientific theory is valid, there must be evidence that it is true (I agree that the evidence can be indirect). This can be done by experiments. The scientist who decided on a theory should conduct an experiment to prove it true, or someone that read the theory can conduct an experiment. Another way to find out if a scientific theory is valid is by checking to see if it follows the laws of thermodynamics, or any other scientific laws known to be true.

mmann said...

We know if a scientific theory is valid when a scientist tests his and his theory follows the rules of the laws of thermodynamics.

Meagan M. said...

One good way to know if a theory is valid is if an experiment has been done to test the theory. this can prove ideas the scientist came up with and provide evidence to persuade the public. Experiments can also disprove earlier findings, which would naturally make the said theory more valid than the other one. Also, a theory can be considered valid if it can be explained in the context of scientific laws.