发布时间:2025-01-31 04:58:24
因为是下水管所以没有底面积,底面周长是2πr=2×3.14×25=157分米,加上接头一共是15.7+0.02=15.72米,所以总面积就是15.72×2=31.44平方米。
如何制作岩棉的消音管给风机用的做一个管道连在风机上降低风机排风时的噪音钢管岩棉
2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24怎么能用12v电瓶能让火花塞点火 请讲明原理 都用什么 怎么接 先谢谢了
2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24 2025-01-31 04:58:24