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An extended object of size 2 mm is placed on the principal axis of a converging lens of focal length 10 cm. It is found that when the object is placed perpendicular to the An extended object of size 2 mm is placed on the principal axis of a converging lens of focal length 10 [...]

6. Saima wants to put a lace on the edge of a circular table cover of diameter 1.5 m. Find the length of the lace required and also find its cost if one meter of the lace costs Rs. 15. (Take π = 3.14) 6. Saima wants to put a lace on the edge of [...]

5.From a circular sheet of radius 4 cm, a circle of radius 3 cm is removed. Find the area of the remaining sheet. (Take π = 3.14) 5.From a circular sheet of radius 4 cm a circle of radius 3 cm is removed. Find the area of the remaining sheet. (Take π = 3.14) October [...]

An object is placed 50 cm from a screen as shown in figure. A converging lens is moved such that line MN is its principal axis. Sharp images are formed on the screen in two positions An object is placed 50 cm from a screen as shown in figure. A converging lens is moved such [...]

4. A gardener wants to fence a circular garden of diameter 21 m. Find the length of the rope he needs to purchase, if he makes 2 rounds of fence. Also, find the costs of the rope, if it cost Rs. 4 per meter. (Take π = 22/7) 4. A gardener wants to fence a [...]

Where should a convex lens of focal length 9 cm be placed ( in cm) between two point sources S1 and S2 which are 24 cm apart, so that images of both the source are formed at the same so that images of both the source are formed at the same Where should a convex [...]

3. If the circumference of a circular sheet is 154 m, find its radius. Also find the area of the sheet. (Take π = 22/7) 3. If the circumference of a circular sheet is 154 m find its radius. Also find the area of the sheet. (Take π = 22/7) October 9, 2020 Category: Chapter [...]

2.Find the area of the following circles, given that: (Take π = 22/7) (c) radius = 5 cm 2.Find the area of the following circles given that: (Take π = 22/7) (c) radius = 5 cm October 9, 2020 Category: Chapter 11 - Perimeter and Area , Maths , NCERT Class 7 ,

A point object is placed at a distance of 25 cm from a convex lens. Its focal length is 22 cm. A glass slab of refractive index 1.5 is inserted between the lens and the object, then A point object is placed at a distance of 25 cm from a convex lens. Its focal length [...]

2.Find the area of the following circles, given that: (Take π = 22/7) (b) diameter = 49 m 2.Find the area of the following circles given that: (Take π = 22/7) (b) diameter = 49 m October 9, 2020 Category: Chapter 11 - Perimeter and Area , Maths , NCERT Class 7 ,