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SUVAT
Teachers Notes
The equations of motion, also known as SUVAT equations, are used when acceleration (a) is constant. They are known as SUVAT equations because they contain the following variables: s - distance, u - initial velocity, v - velocity at time t, a - acceleration and t - time.
Although the videos explain the laws for constant acceleration, there is one interesting law which we thought we should bring to your attention and how it relates to the law of conservation of energy in a closed system.
The law is v = u + 2as
If you multiply both sides by ½m (where m=mass) then we have the formula
½mv = ½mu + 2 x ½mas = ½mu + mas (the 2 and ½ cancel out)
We know that ½mv = The final kinetic energy of object with mass m
We know that ½mu = The initial kinetic energy of the object with mass m
We know what F=ma
We also know that work done = force x displacement (s)
Therefore the formula tells us
The Final Kinetic Energy (½mv )= The Initial Kinetic Energy (½mu )+ the Work Done (mas)
This makes sense. You have an object moving with an initial velocity, you apply work to the object and ots velocity changes.
It is useful for students to understand the formulae as they are widely used throughout Physics.
If you have any queries then please email us.
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Overview Videos
This video gives an overview of the formulae. Note, at the start the narrator makes the point that a constant acceleration is a result of a force applied to an object i.e. Newtons Second Law. The follow on video goes onto explain how the formulae are dereived.
Detail Videos
Although 13 minutes long, this is good revision about the difference between scalar and vector quantities
Revision Videos
Freesciencelessons - Acceleration
Freesciencelessons follows the curriculum and what students need to understand for examination purposes
This video includes examples of resolving vectors. This is good general revision and leads onto SUVAT so are included for completeness.