Question

Consider a syringe whose open end has been sealed, now if we press the piston with our hand, then the pressure inside the syringe will be ____.

• A. higher or lower than atmospheric pressure depending on the force applied
• B. much lower as compared to atmospheric pressure
• C. marginally lower than atmospheric pressure
• D. higher than atmospheric pressure

Answer 1

The correct option is D

higher than atmospheric pressure

Initially when no force is being applied on the piston then the syringe is at equilibrium. That means that the pressure inside the syringe is equal to the external pressure, which is equal to atmospheric pressure. Now pressure due to the force applied by the hand will be in addition to the pre-existing atmospheric pressure. Thus the final pressure inside the syringe will be higher than atmospheric pressure.