Revolving of Right Triangle | CH-13 Surface Area And Volume | Ex 13.7 Q7 to Q9 | Class 9 NCERT

Revolving of Right Triangle | CH-13 Surface Area And Volume | Ex 13.7 Q7 to Q9 | Class 9 NCERT In this video Concept of Right Triangle are explained easily. It helps to clear your doubts/ Concept clearly and helps to cover the question related with Right Triangle In this Lecture, Q7, Q8 and Q9 of Ex 13.7 are covered. Question Covered are:- Q7. A right triangle ABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm.Find the volume of the solid so obtained. Q8. If the triangle ABC in the Question 7 above is revolved about the side 5 cm, then find the volume of the solid so obtained. Find also the ratio of the volumes of the two solids obtained in Questions 7 and 8. Q9. A heap of wheat is in the form of a cone whose diameter is 10.5 m and height is 3 m. Find its volume. The heap is to be covered by canvas to protect it from rain. Find the area of the canvas required. In this video, we are going to learn the Area and Volume of Right triangle concept and formula. This video is being designed in a way to help all classes to learn about triangle . This video is enough to solve any type of problems because we believe in conceptual learning. Share this among your friends and learn Concept of Right Triangle. Welcome to Nand Kishore Classes Click at below links to download the Lectures 1. Basic Math http://nandkishoreclasses.com/basicma... 2. Shortcut Tricks http://nandkishoreclasses.com/shorttr... 3. Kids Activities http://nandkishoreclasses.com/kidsact... 4. Class 4 http://nandkishoreclasses.com/class4 5. Class 5 http://nandkishoreclasses.com/class5 6. Class 8 http://nandkishoreclasses.com/class8 7. Class 9 http://nandkishoreclasses.com/class9 8. Class 10th http://nandkishoreclasses.com/class10 9. Class 11th http://nandkishoreclasses.com/class11 10. Class 12th http://nandkishoreclasses.com/class12 1. Find the volume of the right circular cone with (i) radius 6 cm, height 7 cm (ii) radius 3.5 cm, height 12 cm 2. Find the capacity in litres of a conical vessel with (i) radius 7 cm, slant height 25 cm (ii) height 12 cm, slant height 13 cm 3. The height of a cone is 15 cm. If its volume is 1570 cm3 , find the radius of the base. (Use π = 3.14) 4. If the volume of a right circular cone of height 9 cm is 48 π cm3 , find the diameter of its base. 5. A conical pit of top diameter 3.5 m is 12 m deep. What is its capacity in kilolitres? 6. The volume of a right circular cone is 9856 cm3 . If the diameter of the base is 28 cm, find (i) height of the cone (ii) slant height of the cone (iii) curved surface area of the cone 7. A right triangle ABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. Find the volume of the solid so obtained. 8. If the triangle ABC in the Question 7 above is revolved about the side 5 cm, then find the volume of the solid so obtained. Find also the ratio of the volumes of the two solids obtained in Questions 7 and 8. 9. A heap of wheat is in the form of a cone whose diameter is 10.5 m and height is 3 m. Find its volume. The heap is to be covered by canvas to protect it from rain. Find the area of the canvas required. Question 7. A right triangle ABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. Find the volume of the solid so obtained. Solution: On revolving the right ∆ ABC about the side AB, we get a cone as shown in the adjoining figure. NCERT Solutions for Class 9 Maths Chapter 13 Surface Areas and Volumes Ex 13.7 img 8 ∴ Volume of the solid so obtained = 13 πr2h = 13 x π x 5 x 5 x 4 = 100π cm3 Hence, the volume of the solid so obtained is 100π cm3. Question 8. If the triangle ABC in the Question 7 above is revolved about the side 5 cm, then find the volume of the solid so obtained. Find also the ratio of the volumes of the two solids obtained in Questions 7 and 8. Solution: On revolving the right ∆ ABC about the side BC( = 5 cm), we get a cone as shown in the adjoining figure. NCERT Solutions for Class 9 Maths Chapter 13 Surface Areas and Volumes Ex 13.7 img 9 In above Question 7, the volume V2 obtained by revolving the ∆ ABC about the side 12 cm i.e., V2 = 100π cm3. NCERT Solutions for Class 9 Maths Chapter 13 Surface Areas and Volumes Ex 13.7 img 10 Hence, the required ratio =5:12 Question 9. A heap of wheat is in the form of a cone whose diameter is 10.5 m and height is 3 m. Find its volume. The heap is to be covered by canvas to protect it from rain. Find the area of the canvas required. Solution: NCERT Solutions for Class 9 Maths Chapter 13 Surface Areas and Volumes Ex 13.7 img 11 Facebook Page -   / nandkishoreclasses   YouTube Channel -    / nandkishoreclasses   Instagram -   / nandkishoreclasses   Twitter -   / nandclasses   Website http://nandkishoreclasses.com