Convection and Fluid Dynamics Concepts

What does an ultraviolet torch cause certain objects to do?

• Heat up

• Melt

• Glow or fluoresce

• Change color

Which object was used to demonstrate fluorescence in the video?

• A piece of paper

• A highlighter pen

• A plastic bottle

• A metal rod

What substance in tonic water causes it to fluoresce under ultraviolet light?

• Caffeine

• Quinine

• Salt

• Sugar

What happens to particles in a fluid when they get colder?

• They expand

• They vibrate more

• They get closer together

• They disappear

What is density defined as?

• The amount of weight per unit volume

• The amount of volume per unit mass

• The amount of mass per unit volume

• The amount of space per unit mass

What is the term for the movement of denser fluid downwards and less dense fluid upwards?

• Radiation

• Convection

• Conduction

• Diffusion

What is used in schools to dye water to observe convection currents?

• Sodium chloride

• Iron filings

• Potassium permanganate

• Copper sulfate

What happens to particles when they are heated?

• They stop moving

• They spread out

• They vibrate less

• They contract

What is created when hot particles move up and cooler particles move down?

• A temperature inversion

• A convection current

• A thermal gradient

• A heat wave

What simple model was used to explain convection in the video?

• Marbles

• Lego particles

• Water droplets

• Sand grains