Question

Explain why a rubber sucker pressed on a smooth surface gets stuck to the surface.

Answer 1

A rubber sucker pressed on a smooth surface gets stuck to the surface because of air pressure. When pressed against a flat smooth surface like a wall, air is forced out between the sucker pad and the wall. This reduces the air pressure in the space between the sucker pad and the wall in comparison to the air pressure outside. Hence, greater air pressure outside the sucker pad firmly presses it to the wall.