Table of Contents
Week 1 | KS3 Physics
Week 2 | KS3 Physics
Week 3 | KS3 Physics
Week 4| KS3 Physics
Week 5| KS3 Physics
Week 6| KS3 Physics
Week 7| KS3 Physics
Particle Motion in Gases
- Particles in a gas constantly moving in random directions with random speeds
- Increase temperature = transfer energy into thekinetic energy stores of particles
- Temp of gas is related to the average energy in the kinetic energy stores. Higher temp = higher average energy
- Increase the temp of a gas = average speed of its particles increases
- Gas particles move at high speeds = bang into each other = when they collide with something = exert a force (so pressure) on it.
- In a sealed container = outward gas pressure = total force exerted by all the particles in the gas on a unit area of the container walls
- Faster particles = more frequent collisions =increase in net force and pressure
- Increasing temp = increase speed = pressure increases (if volume is constant)
- Iftemp is constant = increasing the volume of a gas = particles more spread out = hit walls of container less often = gas pressure decreases
- pV= constant (p = pressure = Pa) (V= volume = m³)
- pressure of a gas = causes net outwards force at right angles to surface of its container
- force outside the container = due to pressure of gas around it
- if a container can easily change its size = any change in these pressures = cause the container to compress or expand
- transfer energy by applying a force = do work
- doing work on a gas = increasing internal energy = increasestemperature
- can do work on a gas mechanically
How long have you…? (present perfect 4) Exercises
Use the information given to create questions beginning with ‘How long…?’
• It is snowing.
• The weather is shining.
• John and Kate are married.
• My brother has gone on holiday.
• My aunty and uncle live in Canada.
• My sister is a teacher.
• I work at the chemist.
• I’ve known Susan since I was a baby.
• Jonathan is learning to speak to Mandarin.
Fill in the missing gaps in the sentences using the present perfect (=has/have + past participle)
• I have known Kate a long time.
• My brother has been playing the piano he was 11 years old.
• My mum and dad on holiday to America. They
gone since last Sunday.
• I Ben and Emma since primary school.
We to the same primary and secondary school.
• My sister learning to speak French because she
is going to France next month.
have you lived lives to
has been works have known
I have bought have worked.
• My sister in Spain. She is studying Spanish
with her friend Rosie. I Rosie since I was 5.
• Spencer like with Jamie. They have worked
together for 2 years.
• How long in Australia?
• a new dress for prom.
• He to Thorpe park.
Challenge: Create 4 of your own questions beginning with ‘How long……?’