Show:
The Particle Model
Changing State
Pressure
Floating and Sinking
Drag
100
Name a solid material.
Any correct solids (wood, desk, coffee cup, etc.)
100
What is the name of the change of state when a liquid turns into a solid?
Freeze
100
What is a fluid?
A gas or a liquid.
100
What is upthrust?
A force that pushes things up in liquids and gases.
100

What is drag?

The resistance force caused when an object is moving through a liquid or gas.

200
What happens to the speed of particles as they are heated up?
They move faster.
200
What is the boiling point of water?
100°C
200
What causes pressure in fluids?
The force of particles hitting the container/something in the fluids.
200
What is the density of water?
1 g/cm³
200

Does drag increase or decrease with increasing speed?

Increase

300
How do the forces between particles explain why gases expand to fill their container?
The forces between particles are weak so it is easy for the particles to move around and move apart.
300
Why does the volume of a substance increase as it gets warmer?
Particles vibrate further (for a solid) or move around faster (liquids and gases) so the substance takes up more space.

BONUS: What substance shows anomalous (doesn't fit the pattern) behaviour at freezing point?

300
Name one way to increase the pressure in fluids.
any one from: put more particles into a container, heat the fluid, make the volume of the container smaller
300
What two factors affect you when you float?
upthrust and weight
300
What is a way to reduce drag?
Any one from: make the surface smoother, give it a smooth shape, reduce the area of the object that faces the oncoming fluid

BONUS: What is the word for this?

400
What is the equation triangle for density?
mass/(d*v)
400
Why is evaporation a physical change?
the substances do not change/the atoms in the molecules are not rearranged
400
Why do the walls of submarines need to be so much thicker and stronger than those of boats?
The water pressure increases the further you go down in the ocean.
400

The density of a wood block is 0.7g/cm3. Will it float in water and why?

Yes, because the density is less than 1g/cm3.

400
Why does reducing drag help a car go faster?
The backwards force on the car is less.
500
How does the arrangement and spacing of particles explain why it is difficult to compress solids and liquids?
Particles are already close together, so they cannot be made to go any closer.
500
When a substance is heated, why does the temperature of a substance stop rising as it changes state from a solid to a liquid?
The energy being transferred to the substance is being used to break the particles away from their fixed arrangement.
500
Why does water pressure increase the further a diver goes down in the ocean?
Pressure in fluid depends on the weight of fluid above. As the diver goes down in the ocean there is more water above them and the pressure increases.
500
Why does making the air hotter inside a hot air balloon help the air to rise?
Heating the air in the balloon makes the particles move faster and take up more space (expand), therefore decreasing density to allow the balloon to rise.
500
Why do objects heat up if they are moving fast?
Particles transfer heat energy to the object when they hit it.