Question

How do scientists obtain knowledge about the world?

Answer 1

Well, scientists depend on science.They use the process of observation. But there are processes for these. The processes are;
Asking a question; Scientists wonder how specific happenings can be explained, they look for an answer.
They perform research; the scientists study the  particular thing, and look for reasons for a particular happening.
They form a hypothesis; a hypothesis is a statement which is not universally true, they are observations that haven't been agreed upon.
They test their hypothesis; they perform experiments to find out if their hypothesis is true.
They analyse the data and draw a conclusion; they record their hypothesis and write down their end result.
They pass across their result; they pass their new observation across to other people.
    Hope i helped. Have a nice day. 

Answer 2

Hope this help:)

systematically gathering evidence and discarding potential explanations that do not fit evidence, and refining those that do fit the evidence