1. Raise your hands on your head.
2. Raise your hans over your head.
3. Raise yor hands above your head.
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(What will be the right position after the listeners do as they are told? Are the following positions right?)
In #1, the hands will be on their heads.
In #2, ther hands will be over their heads, not above their heads. (Their hands will be right above their heads.)
In #3, their hands will be above their heads, not over their heads.
Your interpretation of 1 is correct.
The prepositions "over" and "above" mean the same thing in these sentences. There is no difference.
Yes, you are correct in your descriptions of the positions in each of these instructions:
1. In the first instruction, "Raise your hands on your head," the correct position would be to have the hands placed directly on top of the head.
2. In the second instruction, "Raise your hands over your head," the correct position would be to raise the hands above the head. "Over" indicates that the hands are positioned vertically above the head.
3. In the third instruction, "Raise your hands above your head," the correct position would also be to raise the hands vertically upwards, so that they are positioned higher than the head. "Above" indicates a position that is higher than the reference point, in this case, the head.
Therefore, in #2 the hands will be positioned higher than the head, and in #3 the hands will be placed directly above the head.