[vVShabbaVv]

What is the best way of working out which formula to use?

Is there a set way to do it? There sometimes seem like a few ways to work them out but i just don't get it.

[SaintSoldier]

In your head, try and use one equation to solve the problem. If you have too many unknowns, then try another equation. Eventually you'll find the one that works, hence you can solve the problem.

[AeroSpace]

There are five letters: S, U, V, A, T.

Four of them will be relevant to the problem.

Choose the equation which relates those four.

[-Simon-]

Write down everything you know that is given in the question in this form:

u: 16 m/s
a: 2.5m/s^-2
t: 10 s

and then write down what you are looking for i.e. speed

v: ?

Therefore, you need to use v=u+at

[magdaplaysbass]

i always write down the values that i'm already given; then i write down a question mark next the value i'm trying to find. Then i just try and think of the equation that uses the values i have/need.
But yeah, sometimes the question gives you enough information to use more than one suvat; in which case i just pick any

[-strawberry-]

Write down "SUVAT" then next to the thing you need to find, put a question mark. Fill in other things given to you in the question (remember, if it tells you something starts from rest then u=0 and if it is falling down then a=-9.81) cross out the remaining letter. Use the equation that has all four letters shown.

[vVShabbaVv]

Thanks for replying, i appreciate it. I will see how it goes and come back if i'm still stuck.