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
Specific Latent Heat
- Substance is melting or boiling = putting energy in = increasing internal energy = but energy used to break intermolecular bonds rather than raising the temperature. Flat spots on a heating graph = where energy is being transferred by heating but not being used to change the temperature
- Substance is condensing or freezing = bonds are forming between particles = releases energy = internal energy decreases = but temp doesn’t go down until all the substance has turned into a liquid or a solid. Flat parts = show energy transfer
- Energy needed to change state of a substance = latent heat
- Specific latent heat = the amount of energy needed to change 1kg of it from one state to another without changing the temperature
- Cooling = specific latent heat is the energy released by change in state
- SLH is different for different materials and between different states
- SLH for changing between a solid and liquid = specific latent heat of fusion
- SLH for changing between a liquid a gas = specific latent heat of vaporisation
- Energy (joules, J) = mass (kg) X specific heat capacity (J/kg)
- E= mL
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……?’