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प्रश्न
How is scrap iron separated from a heap of waste materials in factories?
उत्तर
Scrap iron is separated from a heap of waste materials in factories by using large electromagnets fitted to a crane. The electromagnet fitted crane is moved up and away from the waste to drop these scrap iron objects at a separate place. Electromagnets are used for this purpose because one can switch on and off the supply of magnetism during the process of lifting and dropping of the iron pieces.
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संबंधित प्रश्न
Define matter.
Explain why steel is used to make railway lines.
Name one element, one compound and one mixture.
Which of the following substances are elements ?
Water, Salt, Mercury, Iron, Marble, Diamond, Wood, Nitrogen, Air, Graphite, Hydrogen, Oxygen, Sugar, Chlorine
Name a metal which has no fixed shape.
What are the three general classes of matter ? Give one example of each type.
Which of the following statements are true for pure substances ?
- pure substances contain only one kind of particles
- pure substances may be compounds or mixtures
- pure substances have the same composition throughout
- pure substances can be exemplified by all elements other than nickel
Out of a colloid, solution and a suspension :
which one has the smallest particles ?
Which of the following will show Tyndall effect ? Why ?
- Salt solution
- Starch solution
- Milk
- Copper sulphate solution
21.5 g of sodium chloride dissolves in 60 g of water at 25°C. Calculate the solubility of sodium chloride in water at that temperature.
Describe the various steps involved in the separation of iodine, iron filings and salt from a mixture.
How is cream separated from milk ?
The dyes present in fountain pen ink can be separated by the technique of :
Justify your answer.
| Figure 1 | Figure 2 | Figure 3 |
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The arrangement of particles in three different phases of matter is shown above.
- Which state is represented by Fig. 1?
- In which state will the inter-particle attraction be maximum?
- Which one of them cannot be contained in an open vessel?
- Which one can take the shape of its container?
All the matter made of ______.
Rusting of an article made up of iron is called
The movement of particles in liquids is ______.
Examples of foam are ______.
Write scientific reason.
Lemon sherbat has sweet, sour and salty taste and it can be poured in a glass.
Define the term matter.
