Acceleration takes place the first 0-30 meters or to about 3-4 seconds from the start of a sprint. After approximately 30 meters acceleration turns into maximum velocity and top speed is hit.
In science, a hypothesis is an idea or explanation that you then test through study and experimentation. Outside science, a theory or guess can also be called a hypothesis. A hypothesis is something more than a wild guess but less than a well-established theory. In science, a hypothesis needs to go through a lot of testing before it gets labeled a theory. In the non-scientific world, the word is used a lot more loosely.
A hypothesis accepted by most scientists, may not be liked or have positive repercussions, but it is one that science has judged likely to be accurate based on the evidence. To learn more about how science judges ideas, visit our series of pages on the topic in our section on how science works.