题干

在“探究凸透镜成像规律”的实验中,凸透镜的焦距为10cm.

(1)调整实验器材,使烛焰和光屏的中心位于凸透镜的主光轴上,如图所示,这样调整的目的是为了____ ;

(2)把点燃的蜡烛由图示位置移至光具座的14cm刻度处时,需将光屏向____ (选填“左”或“右”)移动才能在光屏上成清晰、倒立、____ 的实像;____ 就是利用这一成像规律工作的;

(3)完成实验后,继续模拟远视镜的缺陷,给透镜戴上远视眼镜,调节光屏的位置,使烛焰在光屏上成一个清晰的像;取下远视眼镜,保持蜡烛和凸透镜的位置不变,为使光屏上再次得到清晰的像,应将光屏____ (选填“远离”或“靠近”)透镜.

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答案(点此获取答案解析)

使像能成在光屏的中央 ,左 ,缩小 ,照相机 ,远离 

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