



Chapter 13 Class 10 Surface Areas and Volumes
Example 3 Important
Ex 13.1, 4 Important
Ex 13.1, 9 Important
Example 6 Important
Example 7 Important
Example 9 Important
Example 11 Important
Ex 13.3, 8 Important
Ex 13.3, 9 Important You are here
Example 12 Important Deleted for CBSE Board 2022 Exams
Ex 13.4, 4 Important Deleted for CBSE Board 2022 Exams
Ex 13.4, 5 Important Deleted for CBSE Board 2022 Exams
Surface Area and Volume Formulas Important
Chapter 13 Class 10 Surface Areas and Volumes
Last updated at May 14, 2021 by Teachoo
Ex 13.3, 9 A farmer connects a pipe of internal diameter 20 cm from a canal into a cylindrical tank in her field, which is 10 m in diameter and 2 m deep. If water flows through the pipe at the rate of 3 km/h, in how much time will the tank be filled? Let length of pipe for filling whole tank be h m. So, Volume of pipe = Volume of tank Volume of pipe Pipe is in form of cylinder where Let Height = h m Diameter = 20 cm So, radius = ππππππ‘ππ/2 = 20/2 = 10 cm = 10 Γ 1/100 m = 1/10 m Volume of pipe = Volume of cylinder = πr2h = π(1/10)^2 h = π Γ 1/100 Γ h = πβ/100 Volume of tank Tank is in form cylinder where Diameter = 10 m Radius = r = 10/2 m = 5 m Height = h = 2 m Volume of tank = πr2h = π(5)^2 Γ 2 = π Γ 25 Γ 2 = 50π Now, Volume of pipe = Volume of tank πβ/100 = 50π h = (50π Γ100 )/π h = 5000 m h = 5 km Now, Water in pipe flows at rate 3 km/hr So, 3 km travels in pipe in = 1 hour 1 km travels in pipe in = 1/3 hr 5 km travels in pipe in = 5/3 hr = 5/3 Γ 60 minutes = 5 Γ 20 minutes = 100 minutes. So, in 100 minutes, the tank will be filled