Heat Transfer and Particle Model of Matter (PHYS)

What are the three methods of heat transfer?

Conduction, convection, and radiation.

How do solids conduct heat?

molecular contact, where particles vibrate and pass on heat to neighboring particles.

What is convection in terms of heat transfer?

through density differences in liquids and gases.

What is radiation in terms of heat transfer?

by wave motion that does not require any material.

Why are metals considered good heat conductors?

they have lots of delocalised electrons that move freely, allowing heat to be passed on by vibrating neighboring particles

What is the particle arrangement in solids?

closely packed in neat lines and vibrate in fixed positions.

How do the particle arrangements differ between liquids and gases?

closer together but can move past each other, are widely spaced and move freely.

What is the formula for density?

Density = mass (kg) / volume (m³).

What is the density of water in kg/m³?

1,000 kg/m³.

What is the significance of the temperature difference in heat transfer?

always from hot to cold and only flows where there is a temperature difference.

What is the purpose of a Eureka can in measuring density?

used to measure the volume of irregularly shaped objects by capturing the displaced water.

What is the method for measuring the density of an object using a measuring cylinder?

1. Fill the cylinder with water, 2. Record the initial volume, 3. Weigh the object, 4. Submerge the object, 5. Record the new volume and calculate the difference.

What happens to the density of a substance when it is heated?

decreases its density as it expands.

What is an insulator?

a material that does not conduct heat well.

Why are wooden handles used on metal pans?

they are good insulators, preventing burns while cooking.

How does internal energy relate to the state of matter?

It is the energy stored in a system by the particles, which can change with temperature and state.

What is the relationship between temperature and particle movement?

As it increases, the kinetic energy of particles increases, leading to greater movement.

What is the significance of delocalised electrons in metals?

allow for efficient heat conduction as they can move freely through the metal.

What happens to the potential energy of particles when they are heated?

increases the PE stored in the particles as they move further apart.