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
How We See
- How we see things is due to light reflecting into our eyes.
- Luminous objects produce light =reflects off non luminous objects = reflected light goes into our eyes
- camera =
- Light travels in a straight line from the object to the tracing paper screen through the pinhole.
- As pinhole is small = only one ray gets in from each point on the object.
- Image of the object is upside down and crossed over as the light rays cross over inside the camera.
- Lenses = focus light = refracts light
- Convex lens = bulges outwards = causes light rays to converge (move together ) to a focus
- Human eye = cornea is a transparent window with convex shape = does most of the eyes focusing.
- Convex lens behind the cornea = changes shape = focuses light from objects at varying distances
- Iris = coloured part of the eye = controls the amount of light entering the eye
- Retina = where images are formed = retina cells are photo-sensitive
- Energy is carried by light waves
- Absorber = anything which absorbs this energy
- Energy is transferred to the absorber when energy hits it
- Light waves hit retina cell = causes chemical and electrical changes = sends signals to brain
- Digital camera = light causes sensor to generate an electrical charge = changes in charge read by computer = image
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……?’