Conduction Convection Radiation

In what situation does conduction occur?

• in the absence of particles

• in substances with touching particles

• in fluids

What happens to the particles in a substance as it's being heated?

• They gain energy and vibrate more.

• They gain energy and start to vibrate.

What effect does heating a particle in one part of a substance have on the nearby particles?

• The heated particles transfer radiation to the nearby particles.

• The heated particles collide with nearby particles, causing them to vibrate more as well.

Why doesn't conduction occur in a vacuum?

• There are no particles in a vacuum.

• Energy can't be transferred through a vacuum.

Why does conduction rarely happen in gases?

• There are no particles in gases, so there aren't any collisions.

• The particles are spread out, so the particles rarely collide.

• The particles are closely packed, so they collide often.

Why are frying pans often made from aluminium?

• Metal is a good conductor, so it enables food to quickly.

• Metal is a good insulator, so it enables food to cook quickly.

Why are frying pan handles often made from wood?

• Wood is a good insulator, so it won't burn your hands.

• Wood is a good conductor, so it won't burn your hands.

The particles in a fluid are free to move. Which two states of matter are classed as fluids?

• solid

• liquid

• gas

The density of air depends on its temperature. How does the density of hot air compare to the density of cold air?

• Hot air is more dense than cold air.

• Hot air is less dense than cold air.

• Hot air is the same density as cold air.

Hot air is less dense than cold air. This causes hot air to __________ cold air.

• rise above

• sink below