Sunday, January 29, 2012

Physics Form 4: Chapter 5 - Refraction of Light

  • Refraction is the phenomenon of light bending when it travels from one medium to another medium.
  • Refraction occurs because the velocity of light changes when it travels from a medium into another medium.

The law of refraction states that:
  1. The incident and refracted rays are on opposite sides of the normal at the point of incidence and all three are in the same plane.
  2. The ration of sin i / sin r is a constant. This constant is called refractive index.

Click on the diagram below to play!

Sunday, January 15, 2012

Physics Form 5: Chapter 1 - Shape of the Coastline due to Wave Refraction

  • In the centre of the ocean, the wavefronts are straight and parallel to each other. This is because the water waves travel at uniform speed as the depth of the sea water is uniform.
  • When the waves reach the coast, the water is shallower.
  • Wave speed is reduced and refraction occurs. The wavefronts are refracted and become closer to each other. Wavelength decreases.  
  • Refraction causes the wavefronts to be bent towards the normal.

  • Wave refraction causes wavefronts to parallel the shape of the coastline as they approach shore.
  • Wave refraction also causes wave energy to converge at cape and resulting erosion.
  • Wave energy diverges at bay and spreads out to a wider region, resulting deposition of sand. Therefore, amplitude of waves at the bay is smaller than at the cape.

Monday, January 9, 2012

Penang Science Council Holds ‘2012 Energy Saving Competition’.

SECONDARY school students can bring their imagination to life by designing and constructing a race car model that uses solar energy for the ‘2012 Energy Saving Competition’.The competition, organised by Penang Science Council Malaysia and assisted by Ming Dao University in Taiwan, aims to promote energy and environment conservation among secondary school students in Malaysia.
The council’s Mentoring Young Scientific Entrepreneurs Pillar chairman Datuk Seri Kelvin Kiew said there would be two categories — Solar Model Car Racing Contest and Solar Energy Application Design Competition — which are open to all secondary school students in the country.
He said both events were open to teams of three, and the registration fee is RM100 per person (RM300 per team) per competition.“For the Solar Model Car Racing Contest, each team will be given materials to design and construct their own model,” Kiew told a press conference on Thursday.
“As for the Solar Energy Application Design Competition, participants need to design a model of a product, system or facility that uses solar energy.“Ming Dao University will be sending their experts to educate the students about renewable energy applications throughout their participation in the event.”
Teams can register online at and the closing date is Jan 15 for the Solar Energy Application Design Competition, and Jan 28 for the Solar Model Car Racing Contest.
Kiew said for the design competition, the teams have to submit their design proposal before the closing date.The events will be held at SMJK Heng Ee from Feb 4 to 6. First, second and third placed teams will walk away with RM1,500, RM900 and RM600 respectively, medals and certificates.

Wednesday, January 4, 2012

Welcome Back To School

Today is the first day of schooling in the year of 2012. I have heard many comments from students regarding their first day at school. Even my children also gave the same comment. So boring to come to school ..... so short................

From these comments, our school perception is a BORED PLACE. Sadly to say, sekolah ku rumah ku that used to be a motto in my time is no longer relevant in today student mind.