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1. Why do we slip on ice, but not on wood? The answer is , the force that stops one object
moving against another. When two are in contact, tiny bumps on each surface prevent
them from moving easily. The surface of ice is actually covered in , so your shoes slide
over it. Once you slip, the force of takes over, and you fall down! (friction, gravity,liquid, solid )
2. Nylon was the first material to be produced using coal, water and air. Since its invention
in 1935, it has been used to make many products and long thin strands of it can be made into
for clothing. Although cheap, many people dislike the plastic of nylon
and prefer natural fibres, such as cotton. (fabric, synthetic, texture)
3. Rocks are formed in different ways. One type, metamorphic rocks, are produced by high pressure beneath
the Earth's surface, which the rocks and makes them . Most rocks
are a mixture of different chemicals. When a occurs in rock form but is not mixed with
other chemicals, it is known as a . (compact, firm, mineral, substance)
4. If you take a glass of water and salt in it, you produce what's called a solution. If you add
more water, the solution becomes more . You can the solution by
adding more salt. (concentrate, dilute, dissolve)
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