Understanding Surface Tension

What allows water striders to walk on water?

• Their high density

• Their ability to swim

• Their wings

• Their lightweight and long legs

What is the term for the attraction between water molecules?

• Evaporation

• Diffusion

• Cohesion

• Adhesion

What happens to the forces acting on a water molecule at the surface?

• They are stronger than in the bulk

• They are negligible

• They are only pulled sideways and downwards

• They balance out completely

What is surface tension?

• The force that makes water evaporate

• The process of water freezing

• The phenomenon where the surface of a liquid acts like a stretched film

• The force that makes water molecules repel each other

Why does a paper clip float when placed carefully on water?

• Because it is less dense than water

• Because of surface tension acting like a stretched film

• Because it is magnetic

• Because of air pressure

What happens when a paper clip is dropped into water?

• It dissolves

• It sinks because the surface tension is broken

• It bounces back

• It floats due to its shape

How does surface tension affect the shape of liquid droplets?

• It makes them flat

• It makes them form cubes

• It makes them evaporate

• It pulls them into a spherical shape

What is the geometric shape with the minimum surface area for a given volume?

• Cube

• Cylinder

• Sphere

• Pyramid

What causes the surface of a liquid to act like a stretched film?

• Cohesion between surface molecules and those below

• Gravity

• Wind

• Temperature

Why do certain creatures evolve to take advantage of surface tension?

• To swim faster

• To fly

• To walk on water

• To dive deeper