gravity– tag –

Comparing us on the ground with astronauts in space will definitely helps us to know what we actually do on the ground and what we had better do here on the earth. We will know characteristics of our environment more and well if we know ...

【The reasons for our thinking of the head】 First, I describe here that the reasons why we had better think of our head while we move. Thinking of the head helps us to place the center of gravity of the body at the adequate position and...