Physics Software



Focal length of thin lens





The relationship of focal length, object to lens and lens to image distance shown below. $$\frac{1}{f} = \frac{1}{a} + \frac{1}{b}$$ Here $f$ is focal length, $a$ is lens to object distance, $b$ is lens to image distance. From the equation above the focal length is $$ f = \frac{ab}{a + b} $$ Measure up to 5 set of $a$, $b$ and fill the table below.

Focal length of convex lens

# Distance to object $$a(m)$$ Distance to image $$b(m)$$
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Push on the button for result of the experiment



Focal length of concave lens




# First location of the screen
$ D_1 (m)$		 Second location of the screen
$ D_2 (m)$		 Location of the concave lens
$ O_2 (m)$
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Push on the button for result of the experiment



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