【单选题】【消耗次数：1】
紫外线波长为7.6～400nm。凡是物体温度达到1200℃以上时，辐射光谱中即可出现紫外线，物体温度越高，紫外线的波长越短，强度也越大。（ ）
①
正确
②
错误
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相关题目
【单选题】
阳光中的紫外线照射到皮肤上可生成( )。
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②
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③
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随机题目
【单选题】
楼梯构造不正确的是
①
楼梯踏步的踏面应光洁、耐磨、易于清扫
②
水磨石面层的楼梯踏步近踏口处，一般不做防滑处理
③
水泥砂浆面层的楼梯踏步近踏口处，可不做防滑处理
④
楼梯栏杆应与踏步有可靠连接