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10.1 Understanding energy
The Sun shines on the Using energy
Earth and provides In daily life we often come across the word ‘energy’. When we feel ‘full
it with energy. How of energy’ we run around and have fun until we get tired. Often the
does it do that? How word ‘energy’ is related to the work of vehicles, household devices and
textbooks nis edu kz
is energy transferred power plants. All household devices work thanks to the consumption of
electrical energy. Vehicles consume the energy provided by petrol, while
from the Sun to the
human beings renew their energy reserves by consuming food and
Earth? And think about
drink. Let’s consider what energy is in more detail.
how humans learnt
how to light and warm ACT What words do you normally associate with ‘energy’? Make a mind-
their houses artificially map to visualize the words you already know.
using fires, candles
and lamps. What are Energy as light
Light is one way in which energy
the differences and
is transferred that we see in our
similarities between the
everyday lives. Our main source
energy transfers made of light is the Sun. However, we
by the Sun, the light are able to use light at night-time
bulb and the candle? because we can transfer electrical
energy as light.
Energy as electricity
Electricity can be generated in many ways. We usually generate electrical
energy from other energy transfers through different types of power
stations or with chemical batteries. Electrical energy can be transferred
along metal wires, held up by pylons. We can use electric circuits to
transfer electrical energy for many useful things such as turning on a
television, radio or computer, or charging our mobile phones.
Energy as heat (thermal energy)
Heat is also another way in which we can transfer energy; we use it to
cook our food and to keep us warm when it is cold. We burn fuel to heat
our houses. We also receive heat from the Sun. Fossil fuels are burnt in
power stations to generate electricity.
Energy as chemicals
Living things need energy for growth and sustainability. Plants die
without light energy and chemical nutrients from the soil. Animals and
humans consume plants and other animals as food, and then store and
release all this energy through digestion. Plants process their energy
through photosynthesis.
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