下图中，选择正确的左视图。http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/54f9fbcd45d344d292fb482008cb789f.png
举一反三
- 我国健康成年人血小板总数是（ ）。 A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/fecfc3776aee4bb5b377f5f8f9d9ee46.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/ab64ea1d8d134ba0845fb75e63a9a861.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/4841bf16bdb5469999b7c01b77c90325.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/14d1ed8474e5414591bc74e45bf0538a.png" />
- 假如电子运动速度与光速可以比拟，则当电子的动能等于它静止能量的2倍时，其德布罗意波长约为（ ）m。（普朗克常量<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/486718e348354f0f8706f38073d30016.png" />，电子质量<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/c39decde0930485fa409cb257f712e8a.png" />） A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/e466e61658db48fc816f486d40ae959f.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/3a2fcc4c50a7410e807e4af3c59dcbc8.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/92443a569df04dee9598ae64e6aa3df9.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/21ffd61b214045ceac00daae77f7855f.png" />
- http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/8671406c93434eeab8f0c131ac0dc31a.png
- 如图所示，一束动量为 P 的电子，通过缝宽为<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/b0abb5c99dbc4bec8b8315039bfee3d1.png" />的狭缝，在距离狭缝为 R 处放置一荧光屏，屏上衍射图样中央最大的宽度 d 等于（ ）。<img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/8d94370bc8794b4ebf5f88e8d5bdcf62.png" /> A: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/948caf37e15f4ae1a42fda70c455dcfd.png" /> B: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/07209cdf04d3491b9f214624bc9c0557.png" /> C: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/aa4fab6fa3e74ce6bd96b3e71c40fc30.png" /> D: <img src="http://image.zhihuishu.com/zhs/onlineexam/ueditor/201806/e9fa48b360124287b56d549819645da5.png" />
- 选择正确的左视图。（ ）http://image.zhihuishu.com/zhs/onlineexam/ueditor/201906/b85240588a7f4c138c4ac23da8d2f740.png