试题与答案

小明在学习了透镜后制作一个如图模型照相机,纸筒A的右端蒙了一层半透明纸,纸筒B的

题型:问答题

题目:

小明在学习了透镜后制作一个如图模型照相机,纸筒A的右端蒙了一层半透明纸,纸筒B的左端应该镶嵌一个______(填“凸透镜”或“凹透镜”)当作镜头,他拿着这个模型在较暗的室内,将镜头B对着明亮的室外的景物,拉动纸筒,调节镜头B和半透明纸之间的距离,就可以在半透明纸上看见室外景物______(填“倒立”或“正立”)缩小的实像;此时半透明纸相当于______,如果看近处的景物很清楚,再看远处景物时,应该调节B,______(填“增大”或“缩小”)AB之间的距离.

答案:

(1)照相机的镜头相当于凸透镜,胶片相当于光屏,模型照相机中用半透明的纸做光屏,被照的物体和凸透镜的距离大于2倍焦距,在胶片上能得到倒立、缩小的实像.

(2)如果看近处的景物很清楚,再看远处景物时,物距变大,像要变小,像距也变小,要把两筒间间距缩短,即应该调节B,缩小AB之间的距离.

故答案为:凸透镜;倒立;光屏;缩小.

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题型:单项选择题

Some pioneering work that began as an attempt to discover ways to increase production efficiency led to the founding of the human relations movement in industry and to the development of motivational skills and tools for managers. In 1927 researchers were involved in determining the optimum amount of lighting, temperature, and humidity (with lighting being considered the most important) for the assembly of electronic components at Western Electric. The researchers found that lighting had no consistent effect on production. In fact, production sometimes increased when lighting was reduced to the level of ordinary moonlight! The important part of this experiment began when two Harvard researchers, Elton Mayo and Fritz Roethlisberger, were brought in to investigate these unexpected results further. They found that workers were responding not to the level of lighting but to the fact that they were being observed by the experimenters.
This phenomenon came to be known as the Hawthorne effect since the experiments were conducted at the Western Electric Hawthorne Plant. This was the first documented and widely published evidence of the psychological effects on doing work, and it led to the first serious effort aimed at examining psychological and social factors in the workplace. Further experiments were continued for five years. Generally, the researchers concluded from their experiments that economic motivation (pay) was not the sole source of productivity and, in some cases, not even the most important source. Through interviews and test results, the researchers focused on the effects of work attitudes, supervision, and the peer group and other social forces, on productivity.
Their findings laid the groundwork for modem motivation theory, and the study of human factors on the job, which continues to this day in such common practices as selection and training, establishing favorable work conditions, counseling, and personnel operations. The contributions of this experiment shifted the focus of human motivation from economics to a multifaceted approach including psychological and social forces.

Part of the reason for the change in focus from economics to a more multifaceted approach to the psychological effects on doing work was ______.

A.due to the recognition that workers should be happy at work to maintain high productivity

B.a general conclusion that pay was sometimes not the most important factor

C.because the Hawthorne study continued for so long

D.because the workers requested it

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