Q82.Let A1, A2, A3, … . . be squares such that for each n ⩾1, the length of the side of An equals the length of diagonal of An+1 . If the length of A1 is 12 cm, then the smallest value of n for which area of An is less than one, is = 0 is a
What This Question Tests
The question translates a geometric relationship between successive squares into a geometric progression for their side lengths and then for their areas.
Concepts Tested
Formulas Used
Area of square = side^2
Diagonal of square = side * √2
Formula for nth term of GP: a_n = a * r^(n-1)
📚 NCERT Sections This Tests
2.2 — A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 · Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
9.5 — A Small Bulb Is Placed At The Bottom Of A Tank Containing Water To A
Physics Class 12 · Chapter 9
9.5 A small bulb is placed at the bottom of a tank containing water to a depth of 80cm. What is the area of the surface of water through which light from the bulb can emerge out? Refractive index of water is 1.33. (Consider the bulb to be a point source.)
9.22 — A Card Sheet Divided Into Squares Each Of Size 1 Mm2 Is Being Viewed
Physics Class 12 · Chapter 9
9.22 A card sheet divided into squares each of size 1 mm2 is being viewed at a distance of 9 cm through a magnifying glass (a converging lens of focal length 9 cm) held close to the eye. (a) What is the magnification produced by the lens? How much is the area of each square in the virtual image? (b) What is the angular magnification (magnifying power) of the lens? (c) Is the magnification in (a) equal to the magnifying power in (b)? Explain.
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Geometric progression
- Year
- 2021
- Shift
- 25 Feb Shift 1
- Q Number
- Q82
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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