What is the change of speed over time?

AI Thread Summary
The discussion centers on the concepts of speed, velocity, and acceleration in physics. It clarifies that acceleration is the rate of change of speed over time. The formulas provided are relevant for understanding kinematics under constant acceleration, with one additional formula suggested for further clarity. The participants confirm that these formulas are sufficient for basic kinematics. Overall, the exchange enhances understanding of the relationship between speed, velocity, and acceleration.
pavadrin
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2day i started a new topic inj physics and there were a few terms which i am unsure of. if velocity is the change of displacement over time, and acceleration is the change of velocity, and if speed is the change of distance over time, what is the change of speed over time? also i have come across a few formulas for this topic, these formulas are listed below
s = ut + \frac{1}{2} at^2

v = u + at

v^2 = u^2 - 2as

v_{average} = \frac{s}{t}

a_{average} = \frac{v - u}{t}

are these all the formulas that are required for this topic or are there more? i understand that in some cases they may need to be rearanged.
many thanks,
Pavadrin
 
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The rate of change of speed with respect to time is often termed acceleration, although I do not care for its use. The the formulae you list are valid for constant acceleration in kinematics (except the average acceleration as that obviously can be used universally). The formulae are all that are required for basic kinematics however, there is a further formulae, s = \frac{1}{2}(u+v)t, that may be useful but it is derived from the above formulae.
 
thanks Hootenanny for the relpy and additional formula :smile:
Pavadrin
 
pavadrin said:
thanks Hootenanny for the relpy and additional formula :smile:
Pavadrin
My pleasure :smile:
 
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