A. Sound waves can travel in a vacuum. B. Sound waves are transverse waves. C. The speed of sound waves is constant. D. Sound waves need a medium to travel. 相关知识点: 试题来源: 解析 D。本题考查声音传播的条件。声音的传播需要介质,不能在真空中传播,A 选项错误;声音是纵波,B 选项错误...
百度试题 结果1 题目Air is the medium by which sound waves are ___. A. surveyed B. conveyed C. produced D. made 相关知识点: 试题来源: 解析 B 反馈 收藏
What are electromagnetic waves used for in communication? Which electromagnetic waves are used for communication? How is wavelength measured in electromagnetic radiation? What determines the speed of a wave: the frequency, the wavelength, or the medium through which the wave travels?...
Both light and sound travel in waves. Sound requires a medium through which the waves can travel. For example, sound often travels through air. It can also travel through water or through solid materials. Light does not require a medium to travel....
某建设单位准备建一座图书馆，建筑面积5000m2，预算投资400万元，建设工期为10个月。工程采用公开招标的方式确定承包商。按照《中华人民共和国招标投标法》和《中华人民共和国建筑法》的规定，建设单位编制了招标文件，并向当地的建设行政管理部门提出了招标申请书，得到了批准。 建设单位依照有关招标投标程序进行公开招标...
Top 20 medium airportsFlight cancellations at lowest rates in a decade While there were a few turbulent bumps for airline passengers in 2023, with unexpected delays and cancellations occasionally making headlines due to weather, staffing and growing pains after the COVID-19 slash in travel, the ov...
That sendeth ambassadors by the sea, even in vessels of bulrushes upon the waters, saying, Go, ye swift messengers, to a nation scattered and peeled, to a people terrible from their beginning hitherto; a nation meted out and trodden down, whose land the rivers have spoiled!New King ...
The medium-sized bird is 30—40 centimeters long,with gray wings and a white body.It was first discovered in Indonesia by Polish in 1861.The birds were spotted in 1937 on islands around Qingdao,Shandong Province,and it was not until 2000 that a bird photographer spotted them...
war.To do this,we need to persuade mankind to look upon international questions in a new way,not as contests of force,in which the victory goes to the side which is most skillful in kiting people,but by agreement with principles of law.It is not easy to,change very old mental habits,...
Aquaskipper is a pogo stick for the water which lets you ride wavesDavid Ibekwe