The change in focal length of an eye lens is caused by the action of the

[question] Question. The change in focal length of an eye lens is caused by the action of the (a) pupil (b) retina (c) ciliary muscles (d) iris [/question] [solution] solution: Option (c) is correct. By relaxation or contraction of ciliary muscles, the curvature of the eye lens changes which eventually changes the focal length of eye lens. [/solution]...

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Who among the following is the founder of the Bahujan Samaj Party?

[question] Question. Who among the following is the founder of the Bahujan Samaj Party? Α. Kanshi Ram Β. Sahu Maharaj C. Β.R. Ambedker D. Jotiba Phule [/question] [solution] Solution: Α. Kanshi Ram [solution]...

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The least distance of distinct vision for a young adult with normal vision is about

[question] Question. The least distance of distinct vision for a young adult with normal vision is about (a) 25 m (b) 2.5 cm (c) 25 cm (d) 2.5 m [/question] [solution] solution: Option (c) is correct. The least distance of distinct vision is the minimum distance of an object to see clear image. It is 25 cm for a young adult with a normal vision. [/solution]...

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Two persons manage to push a motorcar of mass 1200 kg at a uniform velocity along a level road.

[question] Question. Two persons manage to push a motorcar of mass 1200 kg at a uniform velocity along a level road. The same motorcar can be pushed by three persons to produce an acceleration of 0.2 ms–2. With what force does each person push the motorcar ? (Assume that all persons push the motorcar with the same muscular effort.) [question] [solution] Solution: As two persons can make the motorcar move with uniform velocity, it is clear that total force applied by them on the motorcar is balan...

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Match List I (organisations and struggles) with List II and select the correct answer using the codes given below the lists:

[question] Question. Match List I (organisations and struggles) with List II and select the correct answer using the codes given below the lists: [/question] [solution] Solution: [/solution]...

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The following is the distance-time table of an object in motion

[question] Question. The following is the distance-time table of an object in motion (a) What conclusion can you draw about the acceleration ? Is it constant, increasing, decreasing or zero ? (b) What do you infer about the force acting on the object? [/question] [solution] Solution: (a) A careful observation of the distance-time table shows that $\mathrm{s} \propto \mathrm{t}^{3}$. It is known that, in uniform motion $\mathrm{s} \propto \mathrm{t}$, and for motion with uniform acceleration $\ma...

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The human eye can focus objects at different distances

[question] Question. The human eye can focus objects at different distances by adjusting the focal length of the eye lens. This is due to (a) presbyopia. (b) accommodation. (c) near-sightedness. (d) far-sightedness. [/question] [solution] solution: Option (b) is correct. Human eye can change the focal length of the eye lens to see the objects situated at various distances from the eye. This ability of eye is called accommodation. [/solution]...

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A group of people who come together to contest elections and hold power in the government is called a ______________________.

[question] Question. A group of people who come together to contest elections and hold power in the government is called a ______________________. [/question] [solution] Solution: A group of people who come together to contest elections and hold power in the government is called a political party. [/solution]...

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What are the characteristics of a political party?

[question] Question. What are the characteristics of a political party? [/question] [solution] Solution: Characteristics of a political party are: The presence of a central ideology which defines what it stands for. Policies arising from this ideology; the party promises to implement these if it is voted to power. The presence of a leader, the party workers and supporters. [/solution]...

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What is the far point and near point of the human

[question] Question. What is the far point and near point of the human eye with normal vision ? [/question] [solution] solution: The far point of a human eye with normal vision is at infinity while the near point is at 25 cm from the eye. [/solution]...

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What is a political party?

[question] Question. What is a political party? [question] [solution] Solution: A political party is a group of people who follow an ideology and thus come together to contest elections and hold power in the government. [/solution]...

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A person with a myopic eye cannot see objects beyond 1.2 m distinctly.

[question] Question. A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of the corrective lens used to restore proper vision ? [/question] [solution] solution: To correct this defect of vision, he must use a concave lens. [/solution]...

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What is meant by power of accommodation of the eye ?

[question] Question. What is meant by power of accommodation of the eye ? [/question] [solution] solution: The ability of the eye lens to adjust its focal length is called power of accommodation. [/solution]...

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Suggest some reforms to strengthen parties so that they perform their functions well?

[question] Question. Suggest some reforms to strengthen parties so that they perform their functions well? [/question] [solution] Solution: Some reforms which could strengthen political parties are: A law should be established to regulate the internal affairs of parties, thereby making them more transparent. Women should be given at least one-third tickets. The state should fund election campaigns, thereby eliminating lobbying groups and unfair competition. [/solution]...

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How much momentum will a dumb-bell of mass 10 kg

[question] Question. How much momentum will a dumb-bell of mass 10 kg transfer to the floor if it falls from a height of 80 cm and does not rebound ? Take its downward acceleration to be 10 ms–2. [question] [solution] Solution: Mass of dumb-bell, $m=10 \mathrm{~kg} ;$ initial velocity, $u=0 ;$ final velocity, $v=? ;$ distance, $\mathrm{s}=80 \mathrm{~cm}=0.8 \mathrm{~m} ;$ acceleration, $\mathrm{a}=10 \mathrm{~ms}^{-2}$ We know $\mathrm{v}^{2}-\mathrm{u}^{2}=2 \mathrm{as}$ $\mathrm{v}^{2}-(0)^{2...

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A doctor has prescribed a corrective lens of power

[question] Question. A doctor has prescribed a corrective lens of power $+1.5$ D. Find the focal length of the lens. Is the prescribed lens diverging or converging ? [/question] [solution] solution: Given, power, $\mathrm{P}=+1.5 \mathrm{D}$ Power, $P=\frac{1}{f}$ or $f=\frac{1}{P}=\frac{1}{+1.5}=\frac{10}{15}=+\frac{2}{3}$ or $\mathrm{f}=+0.66 \mathrm{~m}=+66 \mathrm{~cm}$ The lens is a convex (or converging) lens. [/solution]...

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What are the various challenges faced by political parties?

[question] Question. What are the various challenges faced by political parties? [/question] [solution] Solution: Various challenges faced by political parties: Lack of internal democracy This is caused by the concentration of power in the hands of a few leaders. As a result, positions at the top are reserved for the leaders’ relatives (dynastic succession) or people close to them. Increased dependence on money and muscle power This causes the party policies to be moulded by groups which supply ...

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Find the focal length of a lens of power

[question] Question. Find the focal length of a lens of power $-2.0 \mathrm{D}$. What type of lens is this? [/question] [solution] solution: Given, power, $P=-2.0$ D Power, $P=\frac{1}{f}$ or $f=\frac{1}{P}=\frac{1}{-2}=-0.5 \mathrm{~m}=-50 \mathrm{~cm}$ The lens is a concave (or diverging) lens. [/solution]...

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State the various functions political parties perform in a democracy.

[question] Question. State the various functions political parties perform in a democracy. [/question] [solution] Solution: Functions performed by political parties in a democracy: Group together a large number of similar opinions, thereby providing a direction in which policies can be formulated Contest elections, providing the voters a choice between different policies Winning party forms and runs the government Losing parties form the opposition, and keep a check on the working of the governm...

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An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm.

[question] Question. An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed, so that a sharp, focussed image can be obtained ? Find the size and the nature of the image. [/question] [solution] solution: Given, object height, $\mathrm{h}_{1}=+7 \mathrm{~cm}$; object distance, $\mathrm{u}=-27 \mathrm{~cm}$; focal length, $\mathrm{f}=-18 \mathrm{~cm}$; image distance, $\mathrm{v}=? ;$ image height, $...

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Akhtar, Kiran and Rahul were riding in a motorcar that was moving with a high velocity .

[question] Question. Akhtar, Kiran and Rahul were riding in a motorcar that was moving with a high velocity on an expressway when an insect hit the windshield and got stuck on the windscreen. Akhtar and Kiran started pondering over the situation. Kiran suggested that the insect suffered a greater change in momentum as compared to the change in momentum of the motorcar (because the change in the velocity of the insect was much more than that of the motorcar). Akhtar said that since the motorcar w...

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Mewat is one of the most backward areas in Haryana.

[question] Question. Mewat is one of the most backward areas in Haryana. It used to be a part of two districts, Gurgaon and Faridabad. The people of Mewat felt that the area will get better attention if it were to become a separate district. But political parties were indifferent to this sentiment. The demand for a separate district was raised by Mewat Educational and Social Organisation and Mewat Saksharta Samiti in 1996. Later, Mewat Vikas Sabha was founded in 2000 and carried out a series of ...

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An object 5.0 cm in length is placed at a distance

[question] Question. An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size. [/question] [solution] solution: Given, object distance, $\mathrm{u}=-20 \mathrm{~cm}$; radius of curvature, $\mathrm{R}=+30 \mathrm{~cm}$; height of object, $h_{1}=+5 \mathrm{~cm}$; image distance, $\mathrm{v}=? ;$ magnification, $\mathrm{m}=?$ height of image, $\mathrm{h}_{2}=?$ Focal length, $\mathrm{f}=...

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An object of mass 100 kg is accelerated uniformly from a velocity

[question] Question. An object of mass 100 kg is accelerated uniformly from a velocity of 5 ms–1 to 8 ms–1 in 6 s. Calculate the initial and final momentum of the object. Also, find the magnitude of the force exerted on the object. [/question] [solution] Solution: Mass of object, $\mathrm{m}=100 \mathrm{~kg}$; initial velocity, $\mathrm{u}=5 \mathrm{~ms}^{-1} ;$ final velocity, $\mathrm{v}=8 \mathrm{~ms}^{-1} ;$ time, $\mathrm{t}=6 \mathrm{~s}$ Initial momentum $=\mathrm{mu}=100 \times 5=500 \ma...

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Consider the following statements about pressure groups and parties.

[question] Question. Consider the following statements about pressure groups and parties. Α. Pressure groups are the organised expression of the interests and views of specific social sections. Β. Pressure groups take positions on political issues. C. All pressure groups are political parties. Which of the statements given above are correct? (a) A, B and C (b) A and B (c) B and C (d) A and C [/question] [solution] Solution: (b) A and B [/solution]...

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