Answer:
12.5 m/s
Step-by-step explanation:
The motion of the hammer is a free fall motion, so a uniformly accelerated motion, therefore we can use the following suvat equation:
![v^2-u^2=2as](https://img.qammunity.org/2020/formulas/physics/middle-school/kzr98dbu2wfj2ipzjwf8lasb185fsfra2y.png)
Where, taking downward as positive direction, we have:
s = 8 m is the displacement of the hammer
u = 0 is the initial velocity (it is dropped from rest)
v is the final velocity
is the acceleration of gravity
Solving the equation for v, we find the final velocity:
![v=√(u^2+2as)=√(0+2(9.8)(8))=12.5 m/s](https://img.qammunity.org/2020/formulas/physics/middle-school/j7hmo3ypybuqpyvsrwvmsaxnwdaspb9l56.png)
So, the final speed is 12.5 m/s.