Inspiring Creativity and Curiosity, Making Learning Fun
Science is the study of how the world around us works. Whether in school or here at JustEdu, we believe that repetition and reinforcement serve to aid the retaining of knowledge, helped along with detailed concept maps. We help our students master ACE answering techniques to tackle open-ended questions, making sure that the important keywords are in the answer so that they can score full marks.
The key to engaging students is to stimulate their curiosity and creativity, making learning fun. In fact, our team of passionate and experienced teachers have spent years of doing just that - a passion for science and its applications, whether in everyday life or a faraway future, come in handy to inspire a child to learn more about Science.
When it comes to teaching methodology,
we look towards developing the 5 'E's in each of our students.
These are the five key tenets of Educations.
Here, we engage our students and grab their attention before we start going through the topic by having:
Demonstrations of Experiment
Getting students to ask essential questions
Discussions based on the students' initial understanding of the topic to make connections between past and present learning experiences
Upper Block - Interactions - Adaptations
The diagrams below show an African elephant and an Asian elephant.
Based on the diagrams above, how are the two elephants different?
Explain how this difference is useful for the elephants. (3m)
The African elephant has a larger pair of ears than the Asian elephant. (1m) This increases the surface area exposed to the surroundings (½m) and will help to radiate excess heat from the elephant's body more efficiently (½m) to keep its body cool. (½m) This is necessary as it lives in the African grassland which has a higher average temperature (½m) than the rainforest where the Asian elephant lives.
b) How has the elephant adapted itself to obtain food and water? (2m)
The trunk of the elephant is made up of many strong muscles (½m) that enables it to pick up its food. (½m) The trunk also allows the elephant to suck up water (½m) to blow it into its mouth for drinking. (½m)
Upper Block - Interactions - Forces
"Unlike most mammals, most adult dolphins do not have hair on their bodies other than a few hairs on their beaks which they will lose around the time of birth."
a) How does the lack of hair benefit the dolphin's movement? (1m)
The lack of hair on the skin of the dolphin decreases the surface area in contact with the water, (½m) reducing friction / water resistance. (½m) Hence, the dolphin will be able to swim faster.
b) Explain how wearing a swim cap and a full-body swimsuit enables a swimmer to swim faster. (2m)
Competitive swimmers often put on swim caps and wear full-body swimsuits as shown in the diagram below.
Putting on a swim cap and a full-body swimsuit covers the hair on the swimmer's head and body (1m) which reduces the surface area in contact with the water. (½m) Hence, with reduced friction / water resistance, the swimmer will be able to swim faster. (½m)
Electromagnetic Induction (Sec 4 Physics)
a) There are no transformers that are 100% efficient due to energy loss caused by induced currents in the iron core known as eddy currents.
ai) State the effect that eddy currents have in a transformer.
It causes the transformer to heat up.
aii) Suggest how energy loss due to eddy currents can be reduced.
Use thin sheets of soft iron that is laminated by a layer of insulation.
Although eddy current is not desirable in the design of the transformer, it has been used in the induction stoves.
Induction stoves work by using coils of copper wire placed under a cooking pot which is connected to an alternating current as shown below. This produces an alternating magnetic field which cuts through the cooking pot.
In recent years, induction stoves have been gaining popularity due to the fact that it is much safer than a gas stove. One does not have to worry about getting burnt by the stove during cooking. Even after cooking, the stove remains relatively cool which makes it safe to touch.
bi) Explain how the induction stove is able to heat up the cooking pot.
The constant change in the number of magnetic field lines through the cooking pot induces eddy current in it. This causes large amount of thermal energy to be produced, thus heating up the cooking pot.
bii) With the cooking pot on top of the stove, the induction stove is effectively a step-down transformer as the coil of copper wire has many turns and the cooking pot is effectively a single short turn of coil.
Explain why the induction stove is designed with a step-down configuration
With a step-down configuration, the voltage in the cooking pot is smaller than in the copper wires. This increases the induced current in the cooking pot. As power loss is greater with higher current, most of the electrical energy would be converted to thermal energy in the cooking pot, allowing faster increase in temperature.