CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.6 (#cbsenotes) (#NCERTAnswers)

Surface Areas and Volumes (Cylinder)

EXERCISE 13.6

Q1: The circumference of the base of a cylindrical vessel is 132 cm and its height is 25 cm. How many litres of water can it hold? (1000 cm³ = 1l)

Answer: Given, h = 25 cm, 2πr = 132 cm.
⇒ 2πr = 132
⇒ 2 × (22/7) × r = 132
⇒ r = (132 × 7)/ (2 × 22) = 21cm

Volume = πr²h = (22/7) × 21 × 21 × 25
= 34650 cm³
= 34650/1000
= 34.65 litres  (Answer)


Q2: The inner diameter of a cylindrical wooden pipe is 24 cm and its outer diameter is 28 cm. The length of the pipe is 35 cm. Find the mass of the pipe, if 1 cm³ of wood has a mass of 0.6 g.

CBSE Class 10 - English (Communicative) - SA2- Marking Scheme of Sample Question Paper (2016-17) (#cbseExamPapers)

CBSE Class 10 - SA2 - English (Communicative)- Marking Scheme of Sample Question Paper (2016-17) 

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CBSE Class 8/9/10/11/12: ⑬ Fun Facts about English Words (#englishgrammar) (#cbsenotes)

⑬ Fun Facts about English Words

① The following sentence contains all the alphabets of English (A to Z).

The quick brown fox jumps over the lazy dog 

Such type of sentences are called pangrams. Other examples of pangrams are:

The five boxing wizards jump quickly.

Pack my box with five dozen liquor jugs.

② Pneumonoultramicroscopicsilicovolcanoconioisis (a lung disease) is the longest word in the English language that appears in major dictionaries. Mostly, other longest words are also technical or biological terms.

CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.5 (#cbsenotes) (#ncertsolutions)

Surface Areas and Volumes 

NCERT Exercise 13.5

Q1: A matchbox measures 4 cm × 2.5 cm × 1.5 cm. What will be the volume of a packet containing 12 such boxes?

Answer: Given, l = 4 cm, b = 2.5 cm, h = 1.5 cm
Volume of 1 matchbox = lbh
= 4 × 2.5 × 1.5 cm3 = 15 cm³
Volume of 12 matchboxes = 15 × 12  = 180 cm³ (Answer)


Q2: A cuboidal water tank is 6 m long, 5 m wide and 4.5 m deep. How many litres of water can it hold? (1 m³ = 1000 l)

Answer: Given,  l = 6 m, b = 5 m, h = 4.5 m
Volume of the tank = lbh
= 6 × 5 × 4.5 = 135 m³
= 135 × 1000 litres = 1,35,000 litres (Answer)

CBSE Class 10 - English (Communicative)- Sample Question Paper (2016-17)

CBSE Class 10 - SA2 - English (Communicative)- Sample Question Paper (2016-17) 

☛See Marking Scheme of Class 10  English (Comm.) SQP 2016-17

CBSE Class 9 - Maths - Surface Areas and Volumes (NCERT Ex 13.4) (#cbseclass9notes)

Surface Areas and Volumes - Spheres

(NCERT Ex 13.4)

Q1: Find the surface area of a sphere of radius 
(i) 10.5 cm
(ii) 5.6 cm
(iii) 14 cm

Answer:
(i) r = 10.5 cm
Surface area of the sphere = 4πr²
= 4 × (22/7) × (10.5)²
  = 1386 cm² (Answer)

(ii) r = 5.6 cm
Surface area of the sphere = 4πr²
= 4 × (22/7) × (5.6)²
= 394.24 cm² (Answer)

(iii) r = 14 cm
Surface area of the sphere = 4πr²
= 4 × (22/7) × 14 × 14
= 2464 cm² (Answer)


Q2: Find the surface area of sphere of a diameter :
(i) 14 cm
(ii) 21 cm
(iii) 3.5 m

CBSE Class 12 - English (Elective)- Marking Scheme of Sample Question Paper (2016-17)

CBSE Class 12 - English (Elective)- Marking Scheme of Sample Question Paper (2016-17) 


☛See English (Elective) Sample Question Paper (2016-17)