Why Are My Calculations for Particle Velocity So Inconsistent?

[Brewer]

This is doing my head in. It should be really simple, but I just can't work out the reasons why.

I have a particle of 50g that drops from rest. It drops 1m in 12s.

I then have to find the final velocity of the particle after this 12s.

Using v = u + at I get v=12g

Using h = (u+v)t/2 I get v=1/6.

This is clearly quite a large discrepancy, andI can't see why. Can anyone put me out of my misery with this please?

 

[nicksauce]

There is no discrepency. You are simply just not justified in assuming a value for the acceleration.

 

[Brewer]

Oh ok that's fair enough. Just assumed I could use g. Obviously not then.