Question

in 1897, joseph thomson discovered that atoms contained electrons. he proposed a change in the atomic theory of that time, and the theory was modified because of his discovery. since thomson’s discovery, atomic theory has been further modified/changed. what is the best explanation for why scientific theories are modified/changed? a theories more than ten years old are usually out of date. b new evidence that supports a change prompts scientists to modify/change earlier theories. c scientists want to prove that the work of other scientists is wrong. d so much information is available today that is harder to focus research and disprove theories.

Explanation:

To determine why scientific theories are modified, we analyze each option:

• Option A: The age of a theory doesn't inherently make it out of date; new evidence, not just age, drives changes. So A is incorrect.
• Option B: In science, when new evidence is found that supports a change or contradicts an existing theory, scientists modify the theory to align with the new understanding. This matches how scientific progress works (e.g., Thomson's discovery of electrons led to modifying atomic theory).
• Option C: Scientists aim to build on previous work, not disprove it as a primary goal. The scientific method is about testing and refining, not proving others wrong. So C is incorrect.
• Option D: The availability of information doesn't directly relate to modifying theories; it's new evidence (not just quantity of info) that prompts theory changes. So D is incorrect.

Answer:

B. New evidence that supports a change prompts scientists to modify/change earlier theories.