The correct answer to this question is acceleration. This motion is how fast something is going. It can occur in modes of transportation, like bikes and cars. As one press on the gas pedal, the vehicle will increase in speed. As one brake the bike, the faster the bike will go.
This increase in rate explains the concept of acceleration. The main reason behind acceleration is gravity. Working hand in hand, when gravity increases, so will the acceleration. Two physicists were important behind identifying and explaining the concept of acceleration. The first was Galileo Galilei. Then, a generation later, Isaac Newton further explored the idea.