Question

How does the doctor’s syringe work?

Answer 1

The working of doctor's syringe can be described using the following points:

1. Put the narrow end (needle) of the syringe inside the water or any other liquid (medicine).

2. Push the piston up to its bottom so that all the air from the cylinder comes out through the narrow tube and pressure in the cylinder is reduced.

3. Now pull the piston so that the liquid can rise into the part of the cylinder below the piston.

4. The water does not come out from the syringe as the pressure of the water inside the cylinder is equal to the atmospheric pressure outside.

5. Push the piston in again, to let the water or liquid (medicine) to come out.