Question

Now try some other experiments using the syringe.
After pushing the piston into the syringe, close
the open end of the syringe with your finger.
Then pull the piston back quickly and release it.
Don't you see the piston moving fast into the barrel?
Can you explain its reason?​

Answer 1

Answer:

A vacuum is created in the barrel temporarily. Hence, When the pressure is removed, the piston moves fast to occupy the vacuum.