Answer:
KE = 1.50 J
Step-by-step explanation:
As we know that there is no frictional force here while it is dropped down then in that case we can say that total mechanical energy will remains conserved in it
So here we can say that
![KE + PE = constant](https://img.qammunity.org/2019/formulas/physics/high-school/grg17cxv0waujp8ijqpmfmsmv1dcg97u5p.png)
initially when it is at top the total mechanical energy is in the form of potential energy which is given as 3.00 J
now when it is dropped down by half of the distance then half of the potential energy will remain in it.
So we can say that half of the potential energy will convert into kinetic energy in it
So here we have
![KE = PE = 1.50 J](https://img.qammunity.org/2019/formulas/physics/high-school/olu9who2kqpc0eenc6vdweq9q3a0jou7pd.png)