1. There is a round artifical lake of diameter 82m in a park. There is a path of width 2m surrounding the lake. Find the area of the path surface.(Take "pi"=22/7)
Take the stored value of "pi"in the calculator,and give the answers correct to 2 decimal places if necessary.
2. A cylinder has a base radius of 8cm.It is 12cm high.Find its curved surface area.
3. A cylinder can has a base radius of 5cm and a height of 11cm.Find its capacity in cm^3.
4. A cylindrical bucket without a lid has a base radius of 8cm and a height of 9cm. Find its total surface area.
F.2 Maths
2009-09-02 3:49 am
回答 (1)
2009-09-03 3:03 am
✔ 最佳答案
1. Radius of the lake = 81/2 = 41 mRadius of the outer part of the path = 41 + 2 = 43 m
Area of the path surface
= pi(43)2 - pi(41)2
= (168)(22/7)
= 528 m2
2. Curved surface area = 2pirh
= 2pi(8)(12)
= 603.19 cm2 (2 d.p.)
3. Capacity
= pir2h
= pi(5)2(11)
= 275pi cm3
4. Total surface area
= curved surface area + base area
= 2pi(8)(9) + pi(8)2
= 208pi cm2
參考: Physics king
收錄日期: 2021-04-19 15:16:15
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