Science Notes Essay

Submitted By AidenChan1
Words: 1330
Pages: 6

Science Revision.

Identify situations where waves transfer energy.
Vibration in the air, in the water, in electric and magnetic fields.

Recall that sound is a wave and describe how it is formed and propagates
Sound is a wave and it is formed by a vibrational mechanical energy that propagates through matter as a wave.

Qualitatively describe the features of waves including wavelength, frequency, speed and amplitude.
Frequency: Is the amount of vibrations a wave produces per second measured in hertz,
Amplitude: A sound that is louder has greater amplitude and a softer sound has smaller amplitude.
Speed: The speed is 331 m/s in air at 0 degrees, 342 m/s at 18 degrees, 1440 m/s in water, 4500 m/s in wood, 5100 m/s in steel, 5200 m/s in glass.
Wavelength: The wavelength is the distance between successive peaks.

Use the wave equation to calculate the speed of a wave.
---------------- =c=f/landa Frequency

Identify examples of different types of radiation that make up the EM spectrum and relate these properties to their everyday uses. x rays used in hospitals, Infar red used on scopes of guns, microwaves to heat up food, radio waves to power radios (am and FM)

Compare EM radiation with sound waves
.Unlike electromagnetic radiation , which can travel in the vacuum of free space, sound Waves require a medium (solid, liquid, or gas) in which to travel. Another important difference is that sound travels much slower than electromagnetic radiation; the speed of sound in air at sea level is approximately 1000 ft/sec (300 m/sec), which is roughly a millionth the speed of light in air.

Apply the law of reflection to everyday situations involving waves.
When you see yourself as a reflection in a river and waves come to distort the image an the waves run through the reflection messing it up.

Describe the process of refraction: the bending of light is called refraction. Light refracts when it travels from one transparent substance to another.

Recall that white light is not a pure colour and that it can be dispersed into its spectrum
Shining all colours together produces White.

Recall the principles of additive colour mixing using light.
When a light passes through a glass prism, the exited light is the colour of the rainbow. Newton concluded that light consists of all the colours of the visible spectrum. The colours are red, orange, yellow, green, blue, indigo and violet. When the entire colour shine at once it produces whit light. The splitting of the white light is called dispersion.

Recall the development of models of the atom
Early BCE: The ancient Greeks believed that all matter was made up of four fundamental elements: Air, water, fire, and earth.
460-370 BCE: Democritus suggested that matter was not continuous but made up of tiny, solid and unbreakable particles. He was the first person to use the term 'indivisible'.
1904: JJ Thompson discovered the electron and its negative charge in 1897, how every he knew there must of been a positive charge in the atom to make it neutral. He proposed the Plum Pudding model and it was thought to be made up of a round positive ball of positive charge and electrons embedded in it.
1904: Philip Lenard described atoms as mostly empty space filled with fast-moving 'dynamites'. These were neutrally charged particles made up of a heavy positive particle stuck to a light negative particle.
1911: Ernest Rutherford performed an experiment where he fired a beam of positively charged alpha particles at gold foil. He found that while most of the alpha particles went through the foil, some deflected. This led to the development of the nuclear model, which is most of the mass, is believed to be contained in a small positive nucleus surrounded by a large space occupied by negative electrons.
1913: Niels Bohr modified Rutherford's model and proposed that electrons can only travel