一低压照明系统，系统电源电压及电流瞬时值表达式分别为(314t+30°)V，(314

发布时间：2017-07-20 02:00 │ 来源：www.tikuol.com

题型：问答题

问题：

一低压照明系统，系统电源电压及电流瞬时值表达式分别为

(314t+30°)V，

(314t-30°)A，问：

(1)系统cosα为多大

(2)系统的有功功率户、无功功率Q、视在功率S各为多大

(3)负载的性质

(4)若要提高功率因数到0.95，需要多大Q_c

考点：注册电气工程师供配电专业注册电气工程师(供配电专业)

题型：问答题

阅读理解。

Shakespeare's Birthplace and Exhibition of Shakespeare's World
Welcome to the world-famous house where William Shakespeare was born in l564 and where he grew up.
The property (房产) remained in the ownership of Shakespeare's family until 1806. The House has welcomed
visitors traveling from all over the world, for over 250 years.

OPENING TIMES:
20 Mar to 19 Oct
Mon to Sat: 9:00 a.m. to
5:00 p.m.
Sun: 9:30 a.m. to 5:00 p.m.
20 Oct to 19Mar
Mon to Sat: 9:30 a.m. to
4:00 p.m.
Sun: 10:00 a.m. to 4:00 p.m.

     ◆Enter through the Visitors' Centre and see the highly-
praised exhibition Shakespeare's World, a lively and full
introduction to the life and work of Shakespeare.
     ◆Stand in the rooms where Shakespeare grew up.
     ◆Discover examples of furniture and needlework from
Shakespeare's period.
     ◆Enjoy the traditional (传统的) English garden, planted
with trees and flower mentioned in the poet's works.

ADMISSION:
Adult: ￡4.90
Child: ￡2.20
Family: ￡12.00
(2 adults + up to 3
children)

     The Birthplace is within easy walking distance of all the car
parks shown on the map; nearest is Windsor Street (3 minutes'
Walk).
     ㊣The House may present difficulties but the Visitors' Centre, its
exhibition, and the garden are accessible (可进入的) to wheelchair
users.
     ⊙The Shakespeare Coffee House (opposite the Birthplace).

1. How much is the admission for a family of two grown-ups and two children?

A. ￡9.80.
B. ￡12.00.
C. ￡14.20.
D. ￡16.40.

2. Where is the nearest parking place to Shakespeare's Birthplace?

A. Behind the exhibition hall.
B. Opposite the Visitors' Centre.
C. At Windsor Street.
D. Near the Coffee House.

3. A wheelchair user may need help to enter _____.

A. the House
B. the garden
C. the Visitors' Centre
D. the exhibition hall

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太阳表面温度大约（）

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EDFA有几种泵浦方式？哪种方式转换效率高？哪种噪声系数小

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不按要求检查固定和非固定索具属于什么性质的违章？

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修约后要求小数点后保留二位

35.4150

A．35.44
B．35.43
C．35.42
D．35.40
E．35.45
以下各题修约后的数字各为

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