Question

A rubber sucker, when pressed on a surface sticks to it. Which of the following factors is responsible for this?

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

Answer 1

The correct option is B 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 it.