Physics S3 Flashcards
Explain the three states of matter?
The three states of matter are;
- Solids - the particles are close together vibrating and have strong bonds e.g. Steel, plastic and wood.
- Liquids - The particles can flow easily. They can vibrate quickly and can take the shape of a container e.g. Mercury, petrol and water.
- Gases - The particles are spread out apart. Flow easily - high vibrational energy e.g. Air, helium and chlorine.
What is the formula for density?
Density = mass divided by volume.
What is the effect of speed.
The speed of sound in the air is around 330m/s.
In different mediums it will travel at different speeds.
eg. Air = fast, Iron = slow. Conclusion: the denser the material, the slower sound travels though it.
Speed = distance divided by time.
Give one example of stopping distances used in real life?
You need to know stopping distances when driving a car. The faster the car is travelling, the greater the stopping distance. Another factor that would affect stopping distance would be the condition of the road. It would take longer to stop if the road was wet than if it was dry.
What is the equation for speed?
Speed is distance moved divided by the time taken.
What is Hooke’s Law?
Hooke’s Law
When an elastic object - such as a spring - is stretched, the increased length is called its extension. The extension of an elastic object is directly proportional to the force applied to it:
Force = Spring constant x extension. F = k x e
The spring constant k is different for different objects and materials.
What is velocity?
The velocity of an object is its speed in particular direction.
What is the friction and effect on slowing down vehicles?
Air resistance slows down vehicles like cars and aeroplanes as they move.
The condition of the road surface would also slow you down.
