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CBSE Class 9 Answered

The power of lens are 1.50 .how to find its focal length. And which lens is that.
Asked by Fathimathamanna04 | 20 Dec, 2018, 08:47: PM
answered-by-expert Expert Answer
Focal length is equal to reciprocal of power of lens.
So for this case P= 1/1.5= 0.667m = 66.7cm
Since its power is positive so it would be convex lens.
Answered by Ankit K | 20 Dec, 2018, 10:38: PM

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CBSE 9 - Physics
An object of mass 1kg is falling from the height h=10m.calculate a) the total energy of an object at h=10m b) potential energy of the object when it is at h=4m c) kinetic energy of the object when it is at h=4m d) what will be the speed of the object when it hits the ground
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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CBSE 9 - Physics
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