The power of a lens is 40D, which of the following is the shortest possible object distance to form a real image?

Question

BlackTom AI · Accepted Answer

The lens power is given as 40 diopters, which means the focal length f is f = 1/P = 1/40 m = 0.025 m = 2.5 cm.
For a converging lens, a real image is formed only when the object distance u is greater than the focal length (u > f). If the object is placed closer than the focal length (u < f), the image is virtual.
Option 1: 2.0 cm is less than f (2.5 cm), so it would produce a virtual image, not a real one.
Option 2: 3.0 cm is greater than f, satisfying the condition for a real image; among the given choices, this is the smallest distance that yields a real image.
Option 3: 4.0 cm also gives a real image since u > f, but it is not the shortest possible distance.
Option 4: 5.0 cm likewise yields a real image, but again it is not the shortest.
In summary, to obtain a real image with the smallest object distance given P = 40 D, you choose the smallest u that still exceeds f, which is 3.0 cm.

BN5102 系列测验 2

The power of a lens is 40D, which of the following is the shortest possible object distance to form a real image?

查看解析

登录即可查看完整答案

类似问题

An object is placed 28.8 cm in front of a converging lens with a focal length of 7.4 cm. Calculate the position of the image formed by the lens.Give your answer in cm to 2 decimal places without unitsFor example: 25.00

A student placed an object at various distances, do , from a converging lens. The corresponding image distance ,di, was measured and recorded in the data table below. What is the focal length of the lens?

Determine the image distance for an object placed 38.3 cm from a convex lens having a focal length of 13.4 cm.

In a consumer society, many adults channel creativity into buying things

Economic stress and unpredictable times have resulted in a booming industry for self-help products

People born without creativity never can develop it

A product has a selling price of $20, a contribution margin ratio of 40% and fixed cost of $120,000. To make a profit of $30,000. The number of units that must be sold is: Type the number without $ and a comma. Eg: 20000

更多留学生实用工具

考试浏览器助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单

BN5102 系列 测验 2

The power of a lens is 40D, which of the following is the shortest possible object distance to form a real image?

查看解析

登录即可查看完整答案

类似问题

An object is placed 28.8 cm in front of a converging lens with a focal length of 7.4 cm. Calculate the position of the image formed by the lens.Give your answer in cm to 2 decimal places without unitsFor example: 25.00

A student placed an object at various distances, do , from a converging lens. The corresponding image distance ,di, was measured and recorded in the data table below. What is the focal length of the lens?

Determine the image distance for an object placed 38.3 cm from a convex lens having a focal length of 13.4 cm.

In a consumer society, many adults channel creativity into buying things

Economic stress and unpredictable times have resulted in a booming industry for self-help products

People born without creativity never can develop it

A product has a selling price of $20, a contribution margin ratio of 40% and fixed cost of $120,000. To make a profit of $30,000. The number of units that must be sold is: Type the number without $ and a comma. Eg: 20000

更多留学生实用工具

希望你的学习变得更简单

BN5102 系列测验 2