TextBook Solutions
- How have technical and economic development led to more consumption of resources? Technical and economic development have led to more consumption of resources on account of various factors such as: Technological developmen... 1
- Explain land use pattern in India and why has the land under forest not increased much since 1960-61? Land resources in India are primarily divided into agricultural land, forest land, land meant for pasture and grazing, and waste land. Waste... 1
- What are the biotic and abiotic resources? Give some examples. Biotic Resources: The resources which are obtained from the biosphere and have life are called Biotic Resources. For example, animals and pl... 1
- What steps can be taken to control soil erosion in the hilly areas? In hilly areas, soil erosion can be controlled by ploughing across contour-lines, making use of terrace farming techniques and using strips... 1
- What type of soil is found in the river deltas of the eastern coast? Give three main features of this type of soil. Alluvial Soil is found in the river deltas of the eastern coast. Three features of alluvial soil: Alluvial soils are very fertile. They are... 1
- Name three states having black soil and the crop which is mainly grown in it. Maharashtra, Madhya Pradesh and Chhattisgarh are states having black soil. Cotton is mainly grown in black soil. 1
- In which of the following states is black soil found? (a) Jammu and Kashmir (b) Maharashtra (c) Rajasthan (d) Jharkhand correct option is b) Maharashtra 2
- In which one of the following states is terrace cultivation practised? (a) Punjab (b) Plains of Uttar Pradesh Correct option is d) Uttarakhand 2
- Which one of the following is the main cause of land degradation in Punjab? Correct option is c) Over irrigation Over irrigation is the main cause of land degradation in Punjab 1
- Under which of the following type of resource can tidal energy be put? (a) Replenishable (b) Human-made (c) Abiotic Correct option is a) Replenishable Explaination:: tidal energy can be put in Replenishable type of resource 1
- Which one of the following type of resource is iron ore? (a) Renewable (b) Biotic (c) Flow (d) Non-renewable Correct option is d) Non-renewable Explaination:: iron ore is non-renewable resource 1
- A doctor has prescribed a corrective lens of power +1.5 D. Find the focal length of the lens. Power of lens, P= 1/f P= 1.5D f= 1/1.5 = 10/15 = 0.66 m A convex lens has a positive focal length. Hence, it is a convex lens or a convergin... 1
- Find the focal length of a lens of power -2.0 D. What type of lens is this? Power of lens, P= 1/f P= -2D f= -1/2 = -0.5 m A concave lens has a negative focal length. Hence, it is a concave lens. 1
- An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. https://www.youtube.com/watch?v=meqKmlYN_p8&ab_channel=2Piclasses An object of size 7.0 cm is placed at 27 cm in front of a concave mirror o... 2
- An object 5 cm is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. https://youtu.be/Axatke6lD44 2
- The magnification produced by a plane mirror is +1. What does this mean? The positive sign means image formed by a plane mirror is virtual and erect. Since the magnification is 1 it means that the size of the imag... 1
- An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image. https://yo... 2
- A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram. h... 2
- An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size a... 2
- One-half of a convex lens is covered with a black paper. Will this lens produce a complete image of the object? The convex lens will form complete image of an object, even if its one half is covered with black paper. It can be understood by the followi... 1
- Name the type of mirror used in the following situations. (a) Headlights of a car a) Concave Mirror: This is because concave mirrors can produce powerful parallel beam of light when the light source is placed at their prin... 1
- We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. Range of the distance of the object = 0 to 15 cm from the pole of the mirror. Nature of the image = virtual, erect and larger than the objec... 1
- Which of the following lenses would you prefer to use while reading small letters found in a dictionary? c) A convex lens of focal length 5 cm 2
- No matter how far you stand from a mirror, your image appears erect. The mirror is likely to be d) either plane or convex 2