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- pith ball electroscope 球验电器
- Both the rubber and the pith ball are negatively charged. 橡胶棒和木髓球两者都带负电荷。
- A charged pith ball may be used as a test body to determine whether or not a second body is charged. 一个带电的木髓球可当作一个检验物体，去确定另一个物体是否带电。
- An instrument used to detect the presence, sign, and in some configurations the magnitude of an electric charge by the mutual attraction or repulsion of metal foils or pith balls. 验电器用于如下目的的一种仪器：检验物体是否带电，指示物体是否带电，通过金箔条或木球的互相吸引或排斥测量电荷的强度
- An instrument used to detect the presence,sign,and in some configurations the magnitude of an electric charge by the mutual attraction or repulsion of metal foils or pith balls. 验电器，用于如下目的的一种仪器：检验物体是否带电，指示物体是否带电，通过金箔条或木球的互相吸引或排斥测量电荷的强度。
- the rubber and the pith ball are negatively charged. 这时，橡胶棒和木髓球两者都带负电荷。
- The pith of that theory is serving for people. 那个理论的精髓是为人民服务。
- He singled and went to second on a passed ball. 他击出一垒打，再因对方漏接而跑上二垒。
- That was the pith of his argument. 那就是他论据的要点。
- In cricket, the ball is delivered overarm. 打板球时，要举臂过肩掷球。
- Children love to ball snow up in their hands. 小孩子们喜欢将雪在手里做成球儿。
- He lay back and hit the ball for four. 他向后弯身击中球，得了4分。
- She came out of her room equipped for the ball. 她盛装从房里出来预备到跳舞会去。
- The loss of the ball game stir up much feeling. 球赛输了引起了极大的愤慨。
- The pitcher tends to pitch the ball too high. 这个投球手常把球掷得过高。
- Smith tied into the ball for a home run. 史密斯猛击球取得本垒打。
- He swiped at the ball and missed it. 他向球猛击，但未打中。
- The ball hit the wall and bounced off it. 球打在墙上又反弹回来。
- The ball is filled with gaseous mixture. 那个球充满了气体混合物。
- The leaves of the electroscope slowly diverge. 验电器的叶片慢慢张开。
