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问题 填空题

无论是电磁打点计时器还是电火花打点计时器都使用交流电源的计时仪器，当电源的频率为50Hz时，振针每隔______s 打一个点．现在用打点计时器测定物体的速度，当电源频率低于50Hz时，如果仍按50Hz的时间间隔打一个点计算，则测出的速度数值将比物体的真实数值______．

答案

打点周期与交流电的周期相同，T=

1
f
=0.02s，当电源频率低于低于50Hz时，实际打点周期将变大，而进行计算时，仍然用0.02s，因此测出的速度数值将比物体的真实数值大．

故答案为：0.02，大．

选择题

20世纪80年代我国设置的面积最大的经济特区是 [ ]

A、厦门特区

B、珠海特区

C、汕头特区

D、海南经济特区

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填空题

One is never at a loss for a place to (1) in Malaysia．The country’s cities and major towns have a (2) range of accommodation to suit all tastes and budgets. Most international- (3) hotels cater to total living requirements and as such, one (4) easily find restaurants, entertainment outlets and fitness centres within the (5) complex.
Several resort hotels even have adjoining golf courses and (6) parks with special privileges accorded to hotel guests. Family outings (7) these hotels can be a practical yet fun-filled activity. Guests (8) on longer stays may appreciate the serviced apartments situated within (9) major cities.
Malaysia is also an excellent destination for romantic getaways, (10) for honeymooners seeking an idyllic tropical retreat with (11) amenities. The country’s award-winning island resorts are paradises waiting to be (12) .
For budget-conscious tourists, there is an array of accommodations located (13) to amenities and tourist attractions. Budget accommodations in Malaysia are (14) according to the Orchid Classification Scheme and include hostels, bed (15) breakfast establishments, inns, boarding houses, rest houses and lodging houses. (16) Orchid rating is awarded to tourist accommodations offering basic facilities (17) well as safe and clean premises.
Adventurous souls can try (18) the innumerable value-for-money kampung-style chalets located along popular beaches. Nature (19) seeking communion with nature in Malaysia’s world-famous nature parks such (20) Taman Negara will be amazed by the easy availability of chalets with modern facilities in these areas.
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