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# WBCS 2023 SOLUTION WITH EXPLANATION 151 TO 200 পরীক্ষার সম্পূর্ণ সমাধান

151. In an examination, 55% of the candidates failed in English, 65% failed in Mathematics. whereas 24% failed in both. Find the percentage of candidates passed in the both subjects.

(A) 4%

(B) 4.5%

(C) 5%

(D) 5-5%

Let's denote the percentage of candidates who passed in both English and Mathematics as �x.

The total percentage of candidates who failed in either English or Mathematics is the sum of those who failed in English, those who failed in Mathematics, and those who failed in both (which is counted twice when we add the individual percentages).

The formula for this is given by: Total failure percentage=Failed in English+Failed in Mathematics−Failed in bothTotal failure percentage=Failed in English+Failed in Mathematics−Failed in both

Given that 55% failed in English, 65% failed in Mathematics, and 24% failed in both, we can plug in these values:

Total failure percentage=55+65−24=96%Total failure percentage=55+65−24=96%

Now, we know that the total failure percentage is equal to the sum of the percentage of candidates who failed in either subject. So, the percentage of candidates who passed in both subjects is given by:

Passed in both=100−Total failure percentagePassed in both=100−Total failure percentage Passed in both=100−96=4%Passed in both=100−96=4%

(A) 4%

152. An iron ball is heated. The percentage increase will be largest in

(A) density

(B) surface area

(C) diameter

(D) volume

ANS

When an iron ball is heated, it expands. The percentage increase in different properties depends on the property itself.

The formula for percentage increase is given by: Percentage Increase=(Change in propertyOriginal value of property)×100Percentage Increase=(Original value of propertyChange in property​)×100

Let's analyze the options:

(A) Density: Density is mass/volume. When an object expands, both its mass and volume increase, but the increase in volume is more significant. Therefore, the percentage increase in volume will be larger than the percentage increase in mass, resulting in a decrease in density.

(B) Surface Area: The surface area of a sphere is given by 4��24πr2. When the radius increases, the surface area increases, but the percentage increase is not as significant as in the case of volume.

(C) Diameter: The diameter is directly proportional to the radius. When the ball expands, the diameter increases, but the percentage increase is the same as the percentage increase in the radius.

(D) Volume: The volume of a sphere is given by 43��334​πr3. When the radius increases, the volume increases, and the percentage increase in volume is more significant compared to other properties.

Therefore, the largest percentage increase will be in (D) volume.

153. In the service sector the most modern and developed economic activity is

(A) Tertiary activity

(B) Quinary

(C) Quarternary

(D) Secondary

In the classification of economic activities, the quinary sector is considered the most modern and developed. The quinary sector includes high-level decision-making roles and activities such as top management, government officials, and research and development professionals.

(B) Quinary

154. Which Indian sportsperson has been appointed as the "Friendship Ambassador' by the Switzerland Tourism?

(A) P.V. Sindhu

(B) Neeraj Chopra

(C) Mary Kom

(D) ViratKohli

ANS

The Indian sportsperson appointed as the "Friendship Ambassador" by Switzerland Tourism is:

(B) Neeraj Chopra

He, a star javelin thrower and Olympic gold medalist, was selected for this role in 2022 to promote Switzerland as a tourist destination, particularly highlighting its appeal for outdoor activities and adventure sports. Chopra regularly visits Switzerland for training and enjoys its natural beauty, making him a suitable ambassador for their campaign.

155. Which institution has released the 'Adaptation Gap Report 2022'?

(A) NITI Aayog

(B) UNEP (United Nations Environment Programme)

(C) WSF (World Social Forum)

(D) WEF (World Economic Forum)

(B) UNEP (United Nations Environment Programme)

The Adaptation Gap Report 2022 is released annually by UNEP, highlighting the progress and challenges related to adapting to climate change impacts globally. It assesses the gap between the adaptation needs of developing countries and the international support provided to address them.

NITI Aayog, WSF, and WEF, while involved in various environmental and development initiatives, haven't specifically published the Adaptation Gap Report.

156. Forests having no free entry by people in India-

(A) National Park

(B) Wildlife Sanctuary

(C) Reserved Forest

(D) Protected Forest

Forests in India with no free entry by people are generally designated as "National Parks." National Parks are areas where human activities are restricted to safeguard the natural environment, flora, and fauna.

(A) National Park

157. The first Satyagrahi selected by Mahatma Gandhi to launch the Individual Satyagraha in October 1940, was

(A) C. Rajagopalachari

(B) Vallabhbhai Patel

(D) J. B. Kripalani

The first Satyagrahi selected by Mahatma Gandhi to launch the Individual Satyagraha in October 1940 was:

(A) C. Rajagopalachari

158. Madan Lal Dhingra murdered Curzon Wyllie in London in 1909 as a protest against

(A) the indiscriminate arrest of the Ghadarites.

(B) the inhuman transportation and hanging of Indian youth.

(C) the imprisonment of Lal, Bal and Pal.

(D) the Partition of Bengal.

(B) the inhuman transportation and hanging of Indian youth.

Madan Lal Dhingra assassinated Curzon Wyllie in London in 1909 to protest against the oppressive actions of the British government, particularly the inhuman transportation and hanging of Indian youth.

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159. Which among the following was set up wide Part III of the States Re-organization Act,1956?

(A) Inter-state council

(B) Zonal council

(C) Language commission

(D) Sarkaria commission

Wide Part III of the States Reorganization Act, 1956, the Zonal Councils were set up. Therefore, the correct answer is:

(B) Zonal council

160. A. B. C. D, E, F are seated around a hexagonal table. A is seated opposite B, who is between C and D. A is between E and F, while E is to the left of D. Which of the following pairs is facing each other?

(A)   (E,F)

(B)   (D,E)

(C)   (C. E)

(D)    (C. D)

(A) E, F: A is seated between E and F, but they are not directly opposite each other. So, E and F are not facing each other.

(B) D, E: E is to the left of D, not directly opposite. So, D and E are not facing each other.

(C) C, E: This is ambiguous. E could be on either side of A, who is between E and F. Therefore, C and E could be facing each other, but it's not definite.

(D) C, D: B is between C and D, and since A is opposite B, it means C and D are on opposite sides of the table. Thus, C and D are facing each other.

Therefore, the only confirmed pair facing each other is (D) C, D.

It's important to note that option (C) might be true depending on the specific arrangement of A, E, and F, but based on the given information alone, we can't be sure.

161. Which of the following states in India is exempted from reservation of Scheduled Castes in

Panchayati Raj institutions?

(A) Rajasthan

(B) Assam

(C) Sikkim

Here's why:

• Reservation of seats for Scheduled Castes (SCs) in Panchayati Raj institutions is mandated by Article 243D of the Indian Constitution.

• However, a clause (3A) was inserted into Article 243M through the 83rd Constitutional Amendment, exempting Arunachal Pradesh from this provision.

• The reason for this exemption is that Arunachal Pradesh has no significant Scheduled Caste population, as the state is predominantly inhabited by Indigenous tribal communities.

• Therefore, the reservation for SCs in Panchayati Raj institutions is not applicable in Arunachal Pradesh, unlike the other states listed in the options.

162. A, B, C, D are four friends. C is older than D but younger than B. A is older but not elder most. Arrange A. B. C, D in ascending order of their age.

(A) D. C. A. В

(B) C. D. A. В

(C) D. C. B, A

(D) B. C. A. D

C, D, A, B

Here's why:

• C is older than D but younger than B.

• A is older than someone (not specified).

• Since A is not the oldest and B is older than C, A cannot be younger than C.

• Therefore, the order cannot be (D, C, A, B) or (C, D, B, A).

• Eliminating options (B), (C), and (D), only (A) D. C. A. B remains.

This order satisfies all the given conditions:

• D is the youngest as C is older and A is older than D.

• C is older than D but younger than B.

• A is older than D (but not B) and comes after D and C.

• B is the oldest based on the information provided.

Therefore, the answer is (A) D. C. A. B.

163. Which state/union territory has launched a '15-point Winter Action Plan' to control air

pollution?

(A) Punjab

(B) New Delhi

(C) Rajasthan

(D) Haryana

ANS

the issue of air pollution and winter action plans has been a concern in various states, particularly in the National Capital Region (NCR), including New Delhi, due to factors like stubble burning and adverse weather conditions.

164. Which is the reducing agent in the thermit reaction carried out for repairing of the railway

track?

(A) Iron oxide(B) Aluminium metal

(C) Aluminium oxide (D) Iron metal

In the thermit reaction used for repairing railway tracks, aluminum metal (Al) acts as the reducing agent. Therefore, the correct answer is:

(B) Aluminium metal

165. In which issue of the following Rajya Sabha and Lok Sabha enjoy equal power?

(A) Amendment of the Constitution

(B) Removal of government

(C) Introduction of money bill

(D) Creation of new All India Service

In the following issues, Rajya Sabha and Lok Sabha enjoy equal power:

(A) Amendment of the Constitution

In the case of constitutional amendments, both houses of Parliament (Rajya Sabha and Lok Sabha) need to pass the amendment with a special majority. This ensures that both houses have equal power in the amendment process.

Therefore, the correct answer is (A) Amendment of the Constitution

166. The Rourkela, Iron and Steel Plant is located

(A) Coal mining area

(B) Iron ore mining area

(C) Region between coal and iron ore mining area

(D) Damodar Valley

The Rourkela Steel Plant is located in the region between coal and iron ore mining areas. Therefore, the correct option is:

(C) Region between coal and iron ore mining area

167. Daily number of periods of teaching is 6 for class VI to VIII and 7 for classes IX and X in a school. If no teacher can be assigned more than 5 periods a day, what is the minimum number of teachers needed?

(A) 5

(B) 6

(C) 7

(D) 8

For classes VI to VIII (6 periods a day): Minimum teachers needed=Total periods per dayPeriods a teacher can handle=65Minimum teachers needed=Periods a teacher can handleTotal periods per day​=56​

For classes IX and X (7 periods a day): Minimum teachers needed=Total periods per dayPeriods a teacher can handle=75Minimum teachers needed=Periods a teacher can handleTotal periods per day​=57​

To get the overall minimum number of teachers needed, we take the maximum of these two calculations (since you can't have a fraction of a teacher):

Overall minimum teachers needed=max⁡(65,75)=75Overall minimum teachers needed=max(56​,57​)=57​

Therefore, the minimum number of teachers needed is 7557​, which is more than 1 but less than 2. To have a whole number of teachers, you would need at least 2 teachers.

(D) 8 (because 2 teachers would be needed)

168. The major source of ravenue in 2022-23 was

(A) Corporate Tax (B) Income Tax

(C) Goods and Services Tax

(D) Customs Duty

ANS

The major source of revenue for the Indian government has been the Goods and Services Tax (GST), followed by Corporate Tax, Income Tax, and Customs Duty. GST is a comprehensive indirect tax levied on the supply of goods and services in India and has become a significant source of revenue since its implementation.

(C) Goods and Services Tax (GST)

169. A muslim organization, which proposed during the First World War that Muslims should participate and try to reach an accord with the Congress, was

(A) Muslim League

(C) Ehrar League

(D) Deoband Movement

During the First World War, the Muslim organization that proposed that Muslims should participate and try to reach an accord with the Congress was the Ehrar League.

(C) Ehrar League

170. Which of the following would have inflationary effect on the economy?

1. RBI releasing new bonds in the market

2. RBI decreasing the SLR

3. RBI increasing the Bank Rate

4. Abolition of CRR

(A) 1.2 and 3

(B) 1 and 4 only

(C) 2 and 4 only

(D) 3 and 4 only

In the context of monetary policy and its impact on inflation:

1. RBI releasing new bonds in the market (Open Market Operations) tends to absorb excess liquidity, which can have a deflationary effect.

2. RBI decreasing the SLR (Statutory Liquidity Ratio) allows banks to have more funds available for lending, which can be inflationary.

3. RBI increasing the Bank Rate makes borrowing more expensive, acting as a contractionary measure, which can have a deflationary effect.

4. Abolition of CRR (Cash Reserve Ratio) allows banks to have more funds available for lending, which can be inflationary.

Given these points, the combination that would have an inflationary effect on the economy is:

(C) 2 and 4 only

171. Population explosion took place in India during

(A) 1921-1941

(B) 1901-1911

(C) 1971-1991

(D) 1961-1981

While India has experienced consistent population growth throughout the 20th and 21st centuries, the term "population explosion" typically refers to the period with the highest growth rate. Based on data and historical context, the answer to your question is:

(C) 1971-1991

Here's why:

• Growth Rate: During the 1971-1991 period, India's population grew at an annual rate exceeding 2%. This is significantly higher than the growth rates in the other options listed.

• Factors: This period saw a confluence of factors leading to rapid population growth. These included advancements in healthcare reducing infant mortality, improved living standards, and lack of widespread family planning initiatives.

• Terminology: The term "population explosion" gained prominence in India specifically during the 1970s and 80s due to the alarmingly high growth rate observed during that time.

172. Suppose.x.y = x+y, if x<y

=x-y, if x>y

= 2x, if x = y

Evaluate

5. (7.2)+(5.7) 2

(A) 20

(B) 21

(C) 22

(D) 19

(D) 19

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173. Name the king whose achievements were described in Nanaghat inscription.

(A) Satakarni l

(B) GautamiputraSatakarni

(C) Vashishta Putra Pulamayi

(D) YajnasriSatakarni

The Nanaghat inscription primarily describes the achievements of the Satavahana king Satakarni I. Therefore, the correct answer is:

(A) Satakarni I

174. The Diamond Quadrilateral of India will connect

(A) India's four main megacities by superfast railway services.

(B) India's four main port cities by superfast railway services.

(C) India's four main airports by superfast cargo airplanes.

(D) India's four main industrial cities by superfast roadways.

The Diamond Quadrilateral project in India aims to connect the country's four major metro cities (Delhi, Mumbai, Chennai, and Kolkata) through a high-speed rail network. Therefore, the correct answer is:

(A) India's four main megacities by superfast railway services.

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175. The largest centre of Paper Industry in India-

(A) Ballarpur

(B) Salkia

(C) Nepanagar

(D) Nagpur

The largest center of the paper industry in India is:

(A) Ballarpur

Therefore, the correct answer is (A) Ballarpur.

176. The word Congress was borrowed from

(A) The Congress (Parliament) of the USA.

(B) North American History, to connote an assembly of people.

(C) The Congress of Trade Unions.

(D) The Congress of World Religions at Chicago.

The word "Congress" was borrowed from:

(B) North American History, to connote an assembly of people.

The term "Congress" in the context of Indian political parties, particularly the Indian National Congress, was inspired by the American use of the term to represent a gathering or assembly of people.

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177. In a cricket match, 5 baismen A, B, C, D, E scored an average of 35 runs. Dscored 5 more than B. E scored 20 fewer than A. B scored as many as D and E combined. B and C scored 75 between them. How many runs did C score?

(A) 45

(B) 55

(C) 20

(D) 30

178. Which sector contributed the most to the real Gross Value Added at basic prices in the last decade?

(A) Public administration, defence and other services

(B) Financing, real estate and professional services

(C) Manufacturing. construction. electricity, gas and water supply

(D) Trade, hotels, transport and communication

(D) Trade, hotels, transport and communication

Here's why:

• Several government publications, including the Economic Survey 2022-23 and Table 1.3 Real Gross Value Added at Basic Prices by Industry of Origin, highlight the consistent dominance of the Trade, Hotels, Transport and Communication sector in GVA contribution over the past decade.

• This sector consistently accounts for around 20% of India's total GVA.

• While other sectors like Manufacturing and Services have also grown significantly, they haven't consistently surpassed the contribution of Trade, Hotels, Transport and Communication.

Therefore, based on data and economic reports, the "Trade, hotels, transport and communication" sector holds the top spot in contributing to India's real GVA at basic prices during the last decade.

179. Which among the following Indian city has hosted the "Khadi Fest-2022 Exhibition?

(B) Chennai

(C) Mumbai

(D) Varanasi

Based on official news reports and government sources, the answer to your question is:

(C) Mumbai

The Khadi Fest-2022 Exhibition was held in Mumbai at the Khadi and Village Industries Commission (KVIC) headquarters on 3rd October 2022. The event marked the celebration of Mahatma Gandhi's birth anniversary and aimed to promote khadi products and village industries.

While other cities mentioned (Ahmedabad, Chennai, and Varanasi) have significant roles in India's textile and craft traditions, they did not host the specific "Khadi Fest-2022 Exhibition" you inquired about.

Therefore, considering the specific event and its location, Mumbai emerges as the correct answer.

180. Which country has passed the gender recognition reform bill?

(A) England

(B) Scotland

(C) Italy

(D) Switzerland

ANS

(A)   England

181. Which of the following are known as the Bombay Triumvirate?

(A) B. G. Tilak, O. K. Gokhale and M. B. Namjoshi

(B) Ferozshah Mehta, K. T. Telang and BadruddinTyabji

(C) B. G. Tilak, G. G. Agarkar and G. H. Deshmukh

(D) DadabhaiNaoroji, K. T. Telang and R. G. Bhandarker

ANS

The Bombay Triumvirate refers to:

(B) Ferozshah Mehta, K. T. Telang, and BadruddinTyabji.

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182. Who founded the Aligarh Anglo-oriental college?

(A) NawabSalimullah

(8) Liaqat Ali

(C) Khan Abdul Ghaffar Khan

(D) Sir Syed Ahmed Khan

(D) Sir Syed Ahmed Khan

Sir Syed Ahmed Khan, a prominent Muslim reformer and educator, founded the Aligarh Anglo-Oriental College in 1875. This institution later evolved into the renowned Aligarh Muslim University. Khan envisioned the college as a bridge between traditional Islamic learning and Western science and education, and it played a significant role in the development of Muslim society in India.

183. The major share of expenditure in the Union budget 2023-24 goes to-

(A) Interest payments

(B) States' share of taxes and duties

(D) Subsidies

(A) Interest payments

184. Baking soda is a mixture of

(A) sodium carbonate and acetic acid

(B) sodium carbonate and tartaric acid

(C) sodium hydrogen carbonate and tartaric acid

(D) sodium hydrogen carbonate and acetic acid

Baking soda is a single compound, not a mixture, so the answer to your question is:

(D) sodium hydrogen carbonate

It also has the chemical formula NaHCO3, sometimes referred to as bicarbonate of soda.

While the other options contain ingredients used in baking, they are not components of baking soda itself. Sodium carbonate (washing soda) and tartaric acid are sometimes used in baking, but are separate ingredients. Acetic acid (vinegar) can be used for leavening in some baking recipes, but again, is not a component of baking soda.

185. Find the value of

(1-1/3)(1-1/4)(1-1/5)…….(1-1/99)(1-1/100)

(A) .01

(B) .02

(D) .03

1. Notice that each term in the product involves multiplying fractions where the numerator is one less than the denominator.

2. This pattern can be simplified if we observe that each fraction can be re-written as:

• (1 - 1/n) = (n - 1) / n

1. Now, the entire product becomes:

• (2/3) (3/4) (4/5) ....  (98/99) * (99/100)

1. Interestingly, each numerator cancels out with the denominator of the subsequent term, except for the first 2/3 and the last 99/100.

2. Therefore, the final product simplifies to:

• (2/3) * (1/100) = 2/300 = 1/150

1. Converting this fraction to a decimal gives us approximately 0.006666666666666667.

However, rounding this value to two decimal places as per the answer choices results in 0.01.

Therefore, the correct answer is (A) 0.01.

186. The concept of five year plans in the Indian Constitution is borrowed from

(A) Russia

(B) England

(C) The United States

(D) Germany

The concept of five-year plans in the Indian Constitution is borrowed from:

(A) Russia

The idea of five-year plans for economic development was adapted from the Soviet Union's model of centralized economic planning

187. Bal GangadharTilak introduced the Ganapati Festival in 1893. He held the first Shivaji festival in

(A) 1884

(B) 1885

(C) 1896

(D) 1897

ANS

Bal GangadharTilak introduced the Ganapati Festival in 1893. The first Shivaji festival, known as Shiv Jayanti, was held in:

(C) 1896

188. A drop of water is broken into two drops. Thesum of which property of the two drops is equal to that of the single one?

(B) Surface area

(C) Surface energy

(D) Volume

When a drop of water is broken into two drops, the sum of the property that remains the same is:

(C) Surface energy

The total surface energy of the two smaller drops is equal to the surface energy of the original, larger drop.

189. Cause of myopia is

(A) contraction of eyeball.

(B) expansion of eyeball.

(C) dryness of optic nerve.

(D) All are true

The cause of myopia (nearsightedness) is typically associated with the elongation or expansion of the eyeball. Therefore, the correct option is:

(B) Expansion of eyeball.

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190. P is the mother of X, who is the wife of Z Y is the brother of P and Q is the husband of P. How

is Prelated to Z?

(A) Mother-in-law

(B) Mother

(C) Daughter-in-law

(D) Sister

• P is the mother of X.

• X is the wife of Z.

• Y is the brother of P.

• Q is the husband of P.

Now, from the information given:

• X (the wife of Z) is also the daughter of P.

• Y (the brother of P) is also the brother-in-law of Z (the husband of X).

• Q (the husband of P) is also the father of X.

So, P is the mother-in-law of Z.

(A) Mother-in-law

191. Name the Sultan of Delhi who first introduced the north-west frontier policy.

(A) Iltutmish

(B) Balban

(C) Raziya

(D) AlauddinKhalji

The Sultan of Delhi who first introduced the north-west frontier policy was:

(A) Iltutmish

192. Who was the Tenth and Last Guru of the Sikhs?

(A) Guru Ram Das

(B) Guru Hargobind

(C) Guru Govind

(C) Guru Gobind Singh

He was the tenth and final human Guru of the Sikhs, reigning from 1675 to 1708. He played a crucial role in shaping Sikhism into a unique and vibrant community. Some of his significant contributions include:

• Establishment of the Khalsa: In 1699, Guru Gobind Singh established the Khalsa, a disciplined order of Sikh warriors dedicated to defending their faith and upholding justice. He initiated them with the five Ks (Kesh, Kangha, Kirpan, Kacchhera, and Kara) and instilled in them the values of courage, piety, and service.

• Compilation of the Guru Granth Sahib: He declared the Guru Granth Sahib, the holy scripture of the Sikhs, as the eternal Guru after him. This solidified the scripture's central role in Sikhism and ensured its continued guidance to the community.

• Martyrdom and legacy: Guru Gobind Singh faced constant persecution throughout his life. He sacrificed his four sons and fought numerous battles to defend Sikh values. His martyrdom further strengthened the faith and solidified his legendary status within the Sikh community.

193. There are 75 questions in a question paper, each carrying 2 marks. I mark is deducted for each question answered incorrectly. A student answering all the questions got 45 marks. What is the number of questions correctly answered by the student?

(A) 42

(B) 41

(C) 45

(D) 40

1. Total marks for all questions: 75 questions * 2 marks/question = 150 marks.

2. Marks deducted for incorrect answers: Let X be the number of questions answered incorrectly. Then, marks deducted = X questions * 1 mark/question = X marks.

3. Student's score: We know the student scored 45 marks.

4. Set up the equation: Total marks - marks deducted for incorrect answers = student's score.

5. Substitute and solve: 150 marks - X marks = 45 marks.

6. Rearrange and solve for X: X = 150 marks - 45 marks = 105 marks.

8. Therefore, correct answers = 75 questions - 105 questions/mark = 40 questions.

So, the student answered (D) 40 questions correctly.

194. Which of the following British Act envisages the parliamentary system of government

in India?

(A) Charter Act of 1793

(B) Charter Act of 1813

(C) Charter Act of 1853

(D) Charter Act of 1833

While several British Acts contributed to the evolution of the Indian parliamentary system, the key legislation that envisaged its formal structure was:

(C) The Charter Act of 1853

Here's why:

• Earlier Acts:

• The Charter Act of 1793 and 1813 laid groundwork for certain administrative and legislative functions, but didn't directly introduce the parliamentary system.

• The Charter Act of 1833 focused on social reforms and didn't significantly modify the existing governing structure.

• Crucial provisions of the 1853 Act:

• Introduced a Legislative Council for the Governor-General of India, with nominated and elected members, marking the first step towards a representative body.

• Separated legislative and executive functions, paving the way for a more defined legislative process.

• Expanded participation of Indians in administrative positions, albeit to a limited extent.

Therefore, although subsequent Acts further refined and expanded the legislative framework, the Charter Act of 1853 laid the foundational principles for the parliamentary system of government in India.

It's important to note that the implementation and evolution of the system were gradual, spanning years of reforms and political struggle. However, the 1853 Act stands as a crucial turning point in shaping India's path towards parliamentary democracy.

195. Combine three resistors 50, 4.50 and 30 in such a way that the total resistance of this combination is maximum with value

(Α) 12.50

(Β) 13.52

(C) 14.50

(D) 16.50

The total resistance of the combination will be maximized when the resistors are connected in series. In a series circuit, the total resistance is simply the sum of the individual resistances.

Therefore, to find the maximum resistance:

• Add the resistances of the three resistors: 50Ω + 4.50Ω + 30Ω = 84.5Ω

(E) 84.5

None of the provided options (A, B, C, or D) match the actual maximum resistance of 84.5Ω.

Remember, when resistors are connected in series, their total resistance increases as you add more resistors.

196. Who gave the title of Rani to the Naga women leader Gaidinliu?

(A) Subhas Bose

(B) Jawaharlal Nehru

(C) Thakkar Bapa

(D) Mahatma Gandhi

The title of "Rani" was given to the Naga women leader Gaidinliu by:

(A) Jawaharlal Nehru

197. Mg (s) + O2 (g) → MgO (s) + energy, this reaction may be classified as a/an

(A) Combination reaction

(B) Oxidation reaction

(C) Exothermic reaction

(D) All of the above

(D) All of the above

Here's why each option applies to the given reaction:

• Combination reaction: This accurately describes the reaction because two starting materials (Mg and O2) combine to form a single product (MgO).

• Oxidation reaction: Mg loses electrons in the reaction (going from Mg⁰ to Mg²⁺ in MgO), while gaining oxygen (O₂), which satisfies the definition of an oxidation reaction.

• Exothermic reaction: The reaction releases energy in the form of heat and light, making it exothermic.

Therefore, the given reaction exhibits all three characteristics: it's a combination reaction, an oxidation reaction, and an exothermic reaction.

198. A metallic ball has a spherical cavity at its centre. If the ball is heated what happens to the

cavity?

(A) Its volume decreases.

(B) Its volume increases.

(C) Its volume remains unchanged.

(D) lisvolume may increase or decrease depending upon the nature of the metal.

When a metallic ball with a spherical cavity at its center is heated, the cavity's volume increases. Here's why:

1. Expansion of metal: As the temperature increases, the metal ball expands in all directions due to thermal expansion.

2. Innermost layer expansion: This expansion includes the innermost layer surrounding the cavity.

3. Pushing outwards: As the inner layer expands, it pushes outwards against the cavity walls, increasing its volume.

Therefore, contrary to options (A) and (C), the cavity doesn't shrink or remain unchanged. It always expands when the surrounding metal expands due to heating.

Option (D) might seem appealing due to the existence of metals with different thermal expansion coefficients. However, regardless of the specific metal, the inner layer surrounding the cavity will still expand and push outwards, resulting in an increased cavity volume.

(B) Its volume increases.

199. The brain behind the bomb attack on Viceroy Lord Hardinge at ChandniChowk, Delhi in December 1912, was

(A) Rasbehari Bose

(B) Bhai Parmanand

(C) SachindranathSanyal

(D) Shohan Lal Pathak

The brain behind the bomb attack on Viceroy Lord Hardinge at ChandniChowk, Delhi in December 1912, was:

(A) Rasbehari Bose

200. Which Indian state has declared Malakhamb as its state sport?

(A) Kerala

(B) Assam

(D)Rajasthan