Question

A rubber sucker, when pressed on a surface sticks to it, because:

• A. The suckers have a very strong adhesive which holds it in place
• B. Rubber sucker has some glycerin in it
• C. Atmospheric pressure acts on it externally
• D. Gravitational pull acts on it

Answer 1

The correct option is C

Atmospheric pressure acts on it externally

A rubber sucker, when pressed on a surface creates a partial vacuum as shown in the figure.

Once all the air is pushed out and a vacuum is created, the pressure exerted by the air outside is way more than the pressure inside, and hence it sticks to the surface.