1. If the intensity of a given noise increases two-fold, the noise level in decibels (dB) increases by:
1. 2 dB
2. 6 dB
3. 3 dB
4. 10 dB
यदि किसी दिए गए शोर की तीव्रता दो गुना बढ़ जाती है, तो डेसिबल (dB) में शोर का स्तर बढ़ जाता है:
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Answer 3Explanation: NA ©navclasses
2. Formulation of long term – low emission development strategies by each country was suggested under:
1. Paris agreement
2. Montreal protocol
3. International solar alliance
4. Kyoto protocol
प्रत्येक देश द्वारा दीर्घकालीन-निम्न उत्सर्जन विकास रणनीतियाँ तैयार करने का सुझाव निम्नलिखित था:
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Answer 1Explanation: Paris Agreement: To control emissions
Montreal Protocol: To save ozone from depletion
International Solar Alliance: to use solar energy
Kyoto Protocol: For climate change
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3. Statement I: Emissions of hydrocarbons and carbon monoxide are inherently very low from diesel vehicles.
Statement II: Diesel driven vehicles are inherently more fuel efficient compared to petrol driven vehicles.
1. Both Statement I and Statement II are correct.
2. Both Statement I and Statement II are incorrect.
3. Statement I is correct but Statement II is incorrect.
4. Statement I is incorrect but Statement II is correct.
कथन I: डीजल वाहनों से हाइड्रोकार्बन और कार्बन मोनोऑक्साइड का उत्सर्जन स्वाभाविक रूप से बहुत कम है।
कथन II: डीजल चालित वाहन पेट्रोल चालित वाहनों की तुलना में स्वाभाविक रूप से अधिक ईंधन कुशल होते हैं।
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Answer 1Explanation: > Diesel fuel has more energy per litre than gasoline, and diesel engines are more efficient than gasoline engines, hence diesel cars are more fuel efficient.
> Diesel fuel contains no lead, and emissions of controlled pollutants (carbon monoxide, hydrocarbons, and nitrogen oxides) are lower in diesel cars without a catalyst than in gasoline cars.
> Diesels, on the other hand, have higher NOx emissions and substantially greater particulate matter emissions when compared to petrol cars with a catalyst.
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4. Which of the following sources of energy on combustion produces maximum carbon dioxide per unit of energy output or heat content?
1. Coal (sub bituminous).
2. Natural gas.
3. Diesel fuel and heating oil.
4. Gasoline (without ethanol).
दहन पर ऊर्जा का निम्नलिखित में से कौन सा स्रोत ऊर्जा उत्पादन या ऊष्मा सामग्री की प्रति इकाई अधिकतम कार्बन डाइऑक्साइड उत्पन्न करता है?
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Answer AExplanation: NA ©navclasses
5. Contamination of aquatic environment by polychlorinated biphenyls (PCBs) can originate from:
(A) Sewage effluent
(B) Waste incinerators
(C) Toxic dumps
(D)Thermal power plants
(E) Transport sector
1. (A) (C) (E) only
2. (A) (B) (D) (E) only
3. (B) (C) (D) only
4. (A) (B) (C) only
पॉलीक्लोराइनेटेड बाइफिनाइल (पीसीबी) द्वारा जलीय पर्यावरण का संदूषण उत्पन्न हो सकता है:
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Answer 4Explanation: Utility boilers, industrial boilers, waste incineration, sewage sludge incineration, portland cement manufacture, municipal landfills, and other biological incineration were all sources of PCBs.
An organic chlorine compound having the formula C12H10xClx is known as a polychlorinated biphenyl. Polychlorinated biphenyls were once widely used in electrical equipment, carbonless copy paper, and heat transfer fluids as dielectric and cooling fluids.
PCBs have been related to melanomas, liver cancer, gallbladder cancer, biliary tract cancer, gastrointestinal tract cancer, and brain cancer in human studies, and they may also be associated with breast cancer.
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6. Given below are some metals which are released into the environment from a variety of anthropogenic sources. Identify the metal which has been of serious concern from the point of view of pollution of water bodies.
A. Aluminium
B. Copper
C. Mercury
D. Cadanium
E. Lead
Choose the most appropriate answer from the options given below:
1. B C E
2. A B C E
3. C D E
4. A B E
नीचे कुछ धातुएं दी गई हैं जो विभिन्न मानवजनित स्रोतों से पर्यावरण में छोड़ी जाती हैं। उस धातु की पहचान करें जो जल निकायों के प्रदूषण की दृष्टि से गंभीर चिंता का विषय रही है।
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Answer 3Explanation: Following are more dangerous in context of pollution of water bodies: A. Mercury – Minamata disease.
B. Cadmium – Itai itai disease.
C. Lead – Mental retardation, coma.
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7. Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R) :
Assertion (A): Long term low emission development strategies by each country are crucial to realizing the goals of the Paris agreement.
Reason (R): Nationally Determined Contributions (NDCs) declared by each country are not sufficient to keep the rise in global temperature upto 2°C above the pre-industrial level.
(1) Both (A) and (R) are correct and (R) is the correct explanation of (A).
(2) Both (A) and (R) are correct but (R) is NOT the correct explanation of (A).
(3) (A) is correct but (R) is not correct.
(4) (A) is not correct but (R) is correct.
दावा (ए): पेरिस समझौते के लक्ष्यों को साकार करने के लिए प्रत्येक देश द्वारा दीर्घकालिक कम उत्सर्जन विकास रणनीतियां महत्वपूर्ण हैं।
कारण (आर): प्रत्येक देश द्वारा घोषित राष्ट्रीय स्तर पर निर्धारित योगदान (एनडीसी) वैश्विक तापमान में वृद्धि को पूर्व-औद्योगिक स्तर से 2 डिग्री सेल्सियस ऊपर रखने के लिए पर्याप्त नहीं हैं।
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Answer 1Explanation: Each country’s Nationally Determined Contributions (NDCs) are insufficient to limit global warming to 2°C over pre-industrial levels; thus, each country’s long-term low-emission development strategies are critical to achieving the Paris Agreement’s goals.
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8. Statement I: Hurricanes and typhoons are essentially the same as tropical cyclones.
Statement II: Warm tropical oceans and moist air mass are prerequisites for the development of tropical cyclones.
(1) Both Statement I and Statement II are correct.
(2) Both Statement I and Statement II are incorrect.
(3) Statement I is correct but Statement II is incorrect.
(4) Statement I is incorrect but Statement II is correct.
कथन I: तूफान और टाइफून अनिवार्य रूप से उष्णकटिबंधीय चक्रवातों के समान ही होते हैं। कथन II: उष्णकटिबंधीय चक्रवातों के विकास के लिए गर्म उष्णकटिबंधीय महासागर और नम वायु द्रव्यमान पूर्वापेक्षाएँ हैं।
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Answer 1Explanation: Hurricanes are a type of natural disaster that occurs (tropical cyclones).
Massive tropical cyclonic storm systems with winds reaching 119 km/hr (74 miles/hour) are known as tropical cyclones. In many places of the world, the same phenomenon is known by different names. Hurricanes are named after them in the Atlantic Ocean and the eastern Pacific Ocean. Typhoons in the western Pacific are known as typhoons, while cyclones in the southern hemisphere are known as cyclones.
The steps of creating a hurricane are as follows:
(1) Warm ocean waters (at least 26.5°C [80°F]) must be present in the upper 50 m of the tropical ocean. The warmth of these warm seas is required to keep the tropical cyclone alive.
(2) The atmosphere must cool quickly enough as it rises in altitude to be susceptible to moist convection. Thunderstorm activity permits heat held in ocean waters to be released and used in the development of tropical cyclones.
(3) There must be enough moisture in the mid-troposphere (5 km [3 mi] altitude) to keep thunderstorms going. The further growth of widespread thunderstorm activity is hindered by dry mid-levels.
(4) The disruption must occur at least 500 kilometres [300 miles] from the equator. The presence of the Coriolis force is a necessity for tropical cyclonic storms to form. It’s good to know that the Coriolis effect is zero near the equator and grows north and south of it. The disturbance’s low pressure cannot be maintained without the Coriolis force.
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9. Identify the correct sequence (decreasing order) of lifetimes of the following greenhouse gases in atmosphere:
A. Methane
B. Nitrous oxide
C. Surface ozone
D. CFC-11
Choose the correct answer from the options given below:
(1) (D)>(B) > (A) > (C)
(2) (B) > (D) > (A) > (C)
(3) (B) > (D)>(C) > (A)
(4) (D) > (B)>(C) >(A)
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Answer 2Explanation: NA ©navclasses
10. Statement I: Two sounds of same intensity but different frequency characteristics may appear to be of different loudness.
Statement II: The response of the human ear to noise of different frequencies is not uniform.
(1)Both Statement I and Statement II are correct.
(2)Both Statement I and Statement II are incorrect.
(3) Statement I is correct but Statement II is incorrect.
(4)Statement I is incorrect but Statement II is correct.
कथन I: एक ही तीव्रता की दो ध्वनियाँ लेकिन अलग-अलग आवृत्ति विशेषताएँ अलग-अलग ज़ोर की प्रतीत हो सकती हैं।
कथन II: विभिन्न आवृत्तियों के शोर के लिए मानव कान की प्रतिक्रिया एक समान नहीं होती है।
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Answer AExplanation: Two sounds of equal strength but different frequencies are not regarded as having the same loudness. Sounds with intensities in the range of 1000 Hz to 5000 Hz are perceived as louder by the human ear due to the human ear’s inclination to amplify sounds with frequencies in this range. We can easily assume that the loudest sounds will be interpreted as the most intense.
The loudness of a sound would be more of a subjective response that will change depending on a variety of things. The intensity of a sound is a fairly objective quantity that can be measured with sophisticated gear. Individuals will not perceive the same sound as having the same volume. One aspect that influences the human ear’s responsiveness to sound is age. That’s why grandparents don’t hear as well as they once did.
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