皮皮学，免费搜题
登录
搜题
【判断题】
对于具有简单几何形状,材质均匀分布的物体,其物体重心就是该几何体的几何中心,如球形体的重心即为球心。A.
正确
B.
错误
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【简答题】下列物质N 2 、H 2 O、N a 2 O 2 、CaCl 2 、KOH、NaF中，只含有共价键的物质是_________________，只含有离子键的物质是___________，既含有离子键，又含有共价键的物质是____________。
【单选题】The difference in water spray pattern between the high-velocity tip and low-velocity applicator used with the all-purpose nozzle is due to ______.
A.
a difference in water pressure
B.
the method of breaking up the water stream
C.
the length of the applicator
D.
All of the above
【单选题】What is the phase velocity of a mixture of waves?
A.
The velocity of the individual waves
B.
The velocity of energy flow
C.
The velocity of the modulation
D.
Half the group velocity
【简答题】PHV(peak height velocity)
【简答题】（2）图中②所指的物质是________ ，③所指的物质是___________。
【简答题】flow velocity
【单选题】下列各组物质中，物质之间通过一步反应就能实现图示变化的是 物质编号 物质转化关系 a b c d ① FeCl 2 FeCl 3 Fe CuCl 2 ② NO NO 2 N 2 HNO 3 ③ Na 2 O Na 2 O 2 Na NaOH ④ Al 2 O 3 NaAlO 2 Al Al(OH) 3
A.
①④
B.
①②③
C.
①③④
D.
②④
【单选题】In the velocity parallelogram drawn based on the theorem of composition of velocities,
A.
the absolute velocity is diagonal of the parallelogram formed by the transport velocity and relative velocity.
B.
the transport velocity is diagonal of the parallelogram formed by the absolute velocity and relative velocity.
C.
the relative velocity is diagonal of the parallelogram formed by the transport velocity and absolute velocity.
D.
the algebraic sum of the projections of the absolute velocity, transport velocity and relative velocity on any axis is equal to zero.
相关题目：