Archive for the ‘G9 Int Sci’ Category

The end is near!

Thursday, June 2nd, 2011

For our final week of school we will be doing a couple of things.  Firstly, we will be reflecting on our learning in science over the year as a whole, but this semester in particular.  Use this powerpoint to help guide you. Reflection

In science there are a lot of misunderstandings and misconceptions, often published in the media.  Here is a list of some of them.  Choose some and find out the truth!  Happy researching! Science Misunderstandings and Misconceptions

Exam review

Friday, May 20th, 2011

Check out this post by Mr Goodman for some good resources on reviewing the Waves topic.  And here is a list of interactive websites for review:-

Bonding

Ionic compounds

Naming compounds

Atomic structure, atomic number and mass number and isotopes

Periodic table Jeopardy

Atomic models quiz

Balancing equations battleships

Series of games on naming ionic and covalent molecules

Organelles and cell structures

 

 

Eye see!

Monday, May 16th, 2011

Cow eye dissection by Susan Tansil on flickr

We’ll take a look (ha ha) at the structure of the eye, and learn how it captures light waves so that wecan see.

Eye-diagram

We’ll be able to identify the parts by name and also explain their function.  We’ll understand how the eye is like a camera, and we’ll do an eye dissection.

Lenses and ray diagrams

Thursday, May 12th, 2011

telescope by Waifer X on flickr

Here are links to a couple of sites on ray diagrams.  This first one is factual.  This one is interactive, and covers the different types of image obtained when you place your object various distances from the the lens.  And this site (Thanks for finding it Mr Goodman) is really useful.

Make sure you know the difference between a real and virtual image, an inverted and an upright image, and a magnified and diminished image.

Now that you know all about refraction, and how light bends as it passes through lenses, it’s time to take a look at where we use lenses in our daily (or not so daily) lives.  Microscopes, telescopes, cameras, binoculars, all contain at least one lens.  Your task is to select one application of lenses and do some research on it.  Prepare a glogster poster of your findings.  You must explain what type or types of lenses are present, what refraction has to do with your chosen application, and how it works.  Follow the links here to help get you started.

Total internal reflection

Tuesday, May 10th, 2011

Total internal reflection (TIR) – find out what it is and why it is useful.  Watch this demo:  YouTube Preview Image

Exam review

Thursday, May 5th, 2011

final exam by dcJohn on flickr

3 weeks and counting ….. your semester 2 Integrated Science exam is on Thursday 26th May.  Make sure you check the exam schedule CAREFULLY so that you report in the right place at the right time.

You will need to bring pens, pencils, ruler, eraser and calculator to the exam.  YOU ARE NOT ALLOWED TO BORROW.

Here is the “traffic light” review sheet for semester 2.  USE IT!  Come to tutorials to ask me about anything you don’t understand.  Happy studying 🙂

Grade 9 Integrated Science Learning Outcomes revision sheet May 2011

Grade 10 Integrated Science Learning Outcomes revision sheet – May 2011

 

Refraction

Friday, April 29th, 2011

refraction by the_green_squirrel

All waves refract.  This means that they change speed as they travel from one medium to another.  For example, light waves travel faster in air than they do in water.  This means the pencil in the glass of water looks like the picture on the right.  For a full explanation of refraction, read this.  Hopefully you now understand the concept.  If not, ask this archer fish to explain it to you!

We will do a lab to investigate refraction of light as it passes through glass and perspex, and to determine the refractive indices of these substances.  This handout (thank you Mr Duckworth) explains in more detail. Grade-9-Integrated-Science-Waves-Topic-refraction1

You will be required to submit the data tables, calculations and graphs for this lab only.  Refer to this rubric: FINALRubric DCP

Reflection

Friday, April 29th, 2011

wing mirror by Izzard on flickr

All waves are reflected when they hit a surface or barrier.  The angle at which the wave is reflected is not random, but predictable.  We will investigate angles of incidence (i) and angles of reflection (r) of light waves hitting a plane mirror and try to answer these questions about light and reflection:-

  • Light travels in straight lines.  What evidence can you think of that shows this?
  • What is a virtual image?
  • What does laterally inverted mean?

This link gives some basic information to start with.  This one gives a bit more detail.

Waves questions

Tuesday, April 26th, 2011

The distance between repeating parts of the pattern (the length of each single wave) is known as the wavelength (l).  Wavelengths can be measured from anywhere to the next identical part of the wave.

Frequency is a measure of how often something happens in one second. The symbol of frequency is f and the units are hertz (Hz). The relationship between velocity, frequency and wavelength is:

 Velocity (m/s) = frequency (Hz) x wavelength (m)

Light waves travel much faster than sound waves. The speed of a set of waves can be found by using information about the distance travelled and time taken or from information about the frequency and wavelength.

Distance, speed and time are connected by:

Speed (m/s)   =   Distance (m) / time (s)

Example An echo takes 1.5 s to reflect from the front wall of a school building 250m away. What is the speed of sound in air?

Distance for echo = 2 x 250 m = 500 m                                Time taken   = 1.5 s

Speed = distance/time = 500/1.5 = 333m/s

This method is practical at school only for the measurement of the speed of sound.

Example Capital Radio broadcasts throughout the London area using radio waves of frequency 1548kHz, travelling at 300000km/s. To what wavelength would you tune a radio to receive Capital programmes?

Speed   = 300000km/s = 300000000m/s                  Frequency = 1548 kHz (1 548 000 Hz)

Wavelength = speed/frequency  = 300 000 000/1 548 000 = 194 m 

Using your knowledge of the wave equation, and the relationship between frequency and time [f = 1/T], answer the following questions:-

  1. If the waves in the ocean are timed so that they come to shore every 1.74 seconds, what is the frequency of these waves? (Show your working and don’t forget units).
  2. A radio wave has a frequency of 2 MHz (2 MegaHertz = 2 000 000 Hz). Calculate the time period between successive waves.
  3. A radio station broadcasts with a wavelength of 160m. If the velocity of the radio signal is 3 x 108 m/s, calculate the frequency of the wave. 
  4. If all the 1.2 billion people in China jump up and down at the same time, they will create a shock wave that will travel around the Earth in all directions.  This wave will focus and peak on the other side of the Earth, exactly opposite China (around California).  If the circumference of the Earth is 40 000km and the speed of sound on the Earth’s surface is 2850m/s, calculate how long it will take for California to crumble into the sea due to the shock wave.

Here are some more practice questions for you to try. We will then have an assessment on this next week. Wave equation practice questions

And here are the answers: Grade_9_Integrated_Science_1_docwaves_practice_questions_mark_scheme

What is a wave?

Wednesday, April 20th, 2011

sine wave by bdu on flickr

New topic – yay!  We’ll learn about waves – which is very topical at the moment considering all the earthquakes in Japan.  Before we get on to seismic waves we need to have a basic understanding of what a wave is.  Here are some of the points we’ll try and answer:-

  • What is a wave?
  • What is the difference between transverse and longitudinal waves?
  • What are some examples of transverse and longitudinal waves?
  • What are the amplitude, frequency and wavelength of a wave?

Anatomy of Waves

We’ll then take a look at the wave equation       v = f λ

This shows us the relationship between speed of a wave v, the time it takes for a particle to vibrate up and down, and the distance between successive waves λ.  You’ll need your calculators as we practice solving problems in class.