Editor's Note: The Hyperloop is a totally imaginary transportation device that has captivated entrepreneur Elon Musk, who keeps talking about it. First imagined at least 100 years ago, it would ...

One of the most basic things students do in a physics lab is to collect data and use that to build a model. Most of these models come in the form of a mathematical function. But here is the problem.

A negative gradient shows the rate of “slowing down” or deceleration. Velocity-time graphs show velocity on the vertical axis. Acceleration is still represented by the gradient. Key fact The gradient ...

gradient = \(\frac{change~in~y}{change~in~x} = \frac{change~in~speed}{change~in~time} = \) \( \frac{change~in~metres~per~second}{change~in~seconds}\) = metres per ...