Stepwise evolution and emphasising change
Teaching Guidance for 14-16
Some values tell you how a system will evolve
Teacher Tip: Predicting the future, step by step, depends on knowing the values now and projecting forwards.
Expressed as a relationship, you'd get: quantitynew = quantityold + change
This business of change is so important that it's probably worth rearranging the relationship.
Teacher Tip: Make a point of emphasising that change = quantitynew − quantityold.
Knowing →ainstantaneous and →vinitial(1) allows you to guess what the →vlater(1) will be after a short interval (the longer the interval, the riskier the guess), Δ tinterval(initial(1)_final(1)).
Knowing →vinstantaneous and →dinitial(2) allows you to guess what the →dlater(2) will be will be after a short interval (the longer the interval, the riskier the guess), Δ tinterval(initial(2)_final(2)).
Using these instantaneous values to project forward in this way emphasises the fundamentals of kinematics, and uses the idea of accumulations.