Physical World

Physical world

WAL…about light and how it travels

Answer these questions as best you can

• Does light travel in straight lines or in waves? Explain your answer.

• How fast does light travel?• Does light have a weight?• Can we bend light? If so how?• What questions do I have about light?• In your vocab section write these definitions • Refraction the bending of light through a

transparent object such as a lens or water. • Reflection The bouncing of light off an object• Incidence The angle light hits an object at

Light experiments

• What happens to a laser when aimed through..• Prisms at different angles• A concave lens• A convex lens• A mirror at different angles• Draw your results in your books.

• Teacher demo of how light works, reflection and refraction.

• Show how lenses work and how the human eye works

• Now read science works 2 pgs 36 to 39 and answer the questions on the bottom of page 39.

WAL… about electricity and how circuits work• Vocabulary

• CONDUCTOR of electricity carries the ‘power’ or current from one place to another.

• INSULATORS of current stops the transfer or flow of electrons in a circuit.

Answer these questions• What is electricity?• How is electricity generated in NZ?• What do we use electricity for?• How does electricity move from one place to

another?

Experiments

Using your circuit boards answer these questions.

2. What is a circuit?3. Make a circuit which makes the light bulb glow.4. Draw your circuit using scientific symbols.5. Add a break in your circuit use different materials

to see which materials are conductors and insulators.

6. What materials conduct electricity?7. What materials act as insulators?

1. Now add an extra light bulb into your circuit and draw the circuit using scientific symbols, this is called a series circuit.

• What happened to the light bulbs?

2. Add a switch at different places around the series circuit and draw the diagrams. Record what happens each time you move the switch.

3. Follow the teacher’s instructions to make a parallel circuit using two bulbs, then draw the circuit using scientific symbols.

• What happened to the light bulbs?

• You have now made a parallel circuit with two bulbs.

• add a switch at different places around the parallel circuit and draw the diagrams. Record what happens each time you move the switch.

• Now build a series circuit with two bulbs.

• Now add a variable resister, draw the diagram and record the results.

• Choose an activity from the book and construct a circuit using only the diagram and symbols on page 27

Investigating magnetism and magnetic fields

Predict the North and south poles of these magnets

• What is magnetism?• What materials are

magnetic?• How is magnetism

generated?• If you break a magnet in

half what happens to the poles?

• What are the magnetic fields for each of the magnets on the left?

Investigating magnetsMaking a magnet• ApparatusBar magnet10 paper clips

• Method6. Swipe the paperclip with the

magnet in one direction.7. Use the paperclip to test how

many paperclips it can pick up8. Use the magnet to swipe the

paperclip 10 times in the same direction

9. Repeat step 210.Repeat step 3 this time 1nother

30 times.11.Repeat step 212.Record your results

Answer these questions

1. Do you think the more you swipe the magnet over the paperclip it will increase the strength/force of the magnet?

2. What would happen if you used the other pole of the magnet? Why?

3. What would happen if you rubbed the magnet back and forth over the paperclip? Why?

4. Does your new magnet have poles? Why?

5. What do you think happens to the poles of a magnet if you cut in it half?

6. What do you think happens to the atoms inside the temporary magnet

SOUND

• What is sound?Draw a brainstorm of your

concepts of sound, then write these into a definition. Now check and edit your definition against scientific texts.

Record your URLs used.

• How do we hear sound?

Paste the diagram into your book then use the slide to label the parts of the human ear.

Remember the rules for drawing scientific diagrams.

WAL about… sound and how it travels.

These are the questions that we will be answering during this mini unit….

5.What is sound?6.Ho do we hear sound?7.How do sound waves travel from one place to another?8.How are differences in pitch and volume created?

The Human EarUsing these definitions label the parts of the ear.

• Helix - The in-curve rim of the external ear• Antihelix - A landmark of the outer ear• Lobule - A landmark of the outer ear. The very bottom part of the outer ear• Crest of Helix - A landmark of the outer ear• ExternalAuditory Meatus - or External Auditory Canal. The auditory canal is the

channel through which the sounds are led from the ear outside to the middle ear.• Eardrum - (tympanic membrane) A thin layer of skin at the end of the external ear

canal• Auditory Ossicles - The three small bones in the middle ear, know as the hammer

(malleus), anvil (incus) and stirrup (stapes) which are connected to one another. Together these ossicles are called the ossicular chain. Their purpose is to lead the sound striking the eardrum further into the inner ear

• Oval Window - An opening in the bone between the air filled middle ear cavity and the fluid filled inner ear, and is covered by a thin membrane

• Cochlea - Part of the inner ear that contains part of the hearing organs.• Semicircular Canals - Part of the organ of balance that is part of the inner ear• Eighth Nerve - Nerve that transmits messages from the inner ear to the brain.• Eustachian Tube - A tube connecting the middle ear cavity and the pharynx (back

of the throat). It can be opened by coughing or swallowing, though it is normally closed. The occasional opening of the Eustachian tube is necessary to equalize are in the middle ear cavity.

• http://www.iloveellie.com/understandinghearingimpairment.html

How do sound waves travel from one place to another?

1. Using your finger to tap the water to create waves at one end of the dish. (these are the same as sound waves).

2. Record the pattern of the waves.3. Repeat the experiment this time making waves in the centre of

the dish. 4. Record your results.5. What direction did the waves travel in? Predict what happened

to the waves when they hit the edge of the dish? Predict what would happen to the waves in a round dish? Explain your reasoning. Test your hypothesis.

6. Now add a short ruler to the dish in three different positions. Predict what will happen behind the ruler at each position. Test your theory.

7. Record your results.8. Using the results from your investigation can you make a

generalization (rule) about how sound waves travel.

We are investigating how sound waves travels