Question

1. Give reason to show that none of the numbers given below is a perfect square :

(i) 2162
(ii) 6843
(iii) 9637
(iv) 6598
(v) 640
(vi) 49000
(vii) 3600000

2. Which of the following are squares of even numbers?

(i) 676
(ii) 729
(iii) 1089
(iv) 2304
(v) 5625
(vi) 9216

3. Which of the following are squares of odd numbers?

(i) 484
(ii) 961
(iii) 4225
(iv) 7396
(v) 6241
(vi) 8649

4. Without adding find the sum :

(i) 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19 + 21

(ii) 1 + 3 + 5 + 7 +
+47 +49

(iii) 1 + 3 + 5 + 7 + ................. + 97 +99.

5.
(i) Express 144 as the sum of 12 odd numbers.

(ii) Express 225 as the sum of 15 odd numbers.

6. Write a Pythagorean triplet whose smallest member is :

(i) 6
(ii) 14
(iii) 16
(iv) 20





Help❤️

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Answer 1

Answer:

The following are the physical properties of metal :

1. The physical properties make them useful for many purposes. For e.g. Copper is used in making electric wires, gold is used to make jewellery, stainless steel is used to make pots, pans, etc
2. Metals react with nonmetals to form ionic bonds. For e.g. Sodium Chloride (NaCl)
3. Metals are a good conductor of electricity which means that they can conduct electricity due to the free moving electrons present in them. Copper is used as wiring as it is a good conductor of electricity.
4. Metals have high melting points and high boiling points as they have strong metallic bonds.
5. All metals are physically lustrous. They have a lustre that makes them shine. Gold is used for making jewellery.
6. Metals are hard, they can’t be broken easily and require a lot of energy and strength to break. Iron is used to make cars, buildings, ships, etc.
7. Metals weigh a lot as they have a high density. Metals are heavy for their size.
8. They don’t have flexibility and have tensile strength. Metals can’t be stretched.

I hope this will be help you.