如题[2]图所示的微压计中,管和杯的直径比为d/D,液体的重度γ₁和γ₂已知,试根据读数求出罐中的气体压强p和真空度pv的表达式.

A . 1Hz B . 3Hz C . 4Hz D . 5Hz

<img src='https://img2.soutiyun.com/ask/2020-09-23/969710377220459.jpg' />

<img src='https://img2.soutiyun.com/ask/2020-09-23/969705165087342.png' /> (1)A、B点的相对压强(用kN/m²表示). (2)A、B点的绝对压强(用米水柱高度表示). (3)容器底面上的总压力(相对压力).

<img src='https://img2.soutiyun.com/ask/2020-11-20/974756300521667.png' />

<img src='https://img2.soutiyun.com/ask/2020-07-23/964360362330938.png' />

对于 如题3-6图所示的三角波信号，试证明其频谱函数为<img src='https://img2.soutiyun.com/ask/2020-07-10/963220577029868.png' />。 <img src='https://img2.soutiyun.com/ask/2020-07-10/963220592031727.png' />

<img src='https://img2.soutiyun.com/ask/2021-02-14/982166606288733.png' /><img src='https://img2.soutiyun.com/ask/2021-02-14/982166546524315.png' />设小球的半径和线的质量都可以忽略不计，求每个小球所带的电量。

<img src='https://img2.soutiyun.com/ask/2021-02-14/982167363192026.png' />

如题[84]图所示为水电站压力输水管,其直径d=1m,静水头h=100m,试求:(1)当钢管的允许拉应力[σ]=1.37×10⁵kN/m³时,管壁的厚度δ.(2)当管壁的厚度δ=5mm时,管壁的环向与轴向拉应力. <img src='https://img2.soutiyun.com/ask/2020-09-23/96971114423233.jpg' />

<img src='https://img2.soutiyun.com/ask/2020-09-24/969810909876738.jpg' />

<img src='https://img2.soutiyun.com/ask/2020-09-23/969711107286217.jpg' />

由下式给出：<img src='https://img2.soutiyun.com/ask/2020-07-14/963589443855635.png' />。 分析:应用安培环路定理求解。注意环路中电流的计算，应该是先求出载流导体内电流密度，再求出穿过环路的电流。 <img src='https://img2.soutiyun.com/ask/2020-07-14/963589465464871.png' />

<img src='https://img2.soutiyun.com/ask/uploadfile/5514001-5517000/44eda15f76814f90ba87afe93fcd24e7.jpg' /> <img src='https://img2.soutiyun.com/ask/uploadfile/5514001-5517000/6a6f810e99c0d536ad70422b2859afe5.jpg' />

<img src='https://img2.soutiyun.com/ask/2021-01-13/979382023144195.png' />

<img src='https://img2.soutiyun.com/ask/2020-07-22/964277774421394.png' />

有一如[例36]图所示的管路.首先由直径d₁缩小到d₂、然后又突然扩大到直径d₁.已知d₁=20cm,d₂=10cm,U形水银比压计中读数h=50cm,试求管中的流量Q. <img src='https://img2.soutiyun.com/ask/2020-09-24/96981695466348.jpg' />

<img src='https://img2.soutiyun.com/ask/2020-09-23/969706337375393.png' />

<img src='https://img2.soutiyun.com/ask/2020-08-21/966849722889436.png' />

<img src='https://img2.soutiyun.com/ask/2020-09-23/969707124888437.png' />

圆柱筒直径d=2m,长L=1m,重G=19.5kN,静止于贮液容器中,如题[80]图所示,容器中有两种液体,γ=(2/3)γ₂=8kN/m³.h₁=h₂=1m,求切点A和B的支座反力R_A、和R_B. <img src='https://img2.soutiyun.com/ask/2020-09-23/969710974601628.jpg' />

<img src='https://img2.soutiyun.com/shangxueba/ask/18309001-18312000/18309586/2017041816393254717.gif' /> A．增生性筋膜炎 B． 结节性筋膜炎 C． 炎性肌纤维母细胞瘤 D． 纤维瘤病 E． 纤维肉瘤

(1)ab两端的电势差: (2)cd两点电势高低的情况， <img src='https://img2.soutiyun.com/ask/2020-12-28/978022070269893.png' />

0.6m,试求盖板.上受到的总压力。 <img src='https://img2.soutiyun.com/ask/2020-07-21/964193669351486.png' />