Environment & Misc Science — MPSC PYQ
Every Environment & Misc Science question MPSC has actually asked in Science & Technology, 2013–2023 — 13 questions, each with the correct answer from the official MPSC key and a full explanation. Newest papers first.
खालीलपैकी कोणते विधान बरोबर आहे ? Which of the following statement is correct ?
According to Kepler's second law (Law of Areas), a planet moves faster when it is closer to the sun (perihelion) and slower when it is farther away (aphelion).
खालीलपैकी कोणती विधाने चूक आहेत ? / Which of the following are incorrect statements ?
(a)जिवाणूंच्या नॉनएरोबिक अपघटनाला, एरोबिक अपघटनापेक्षा प्राधान्य दिले जात नाही. / A non-aerobic decomposition is not preferred over an aerobic decomposition by bacteria.
(b)सरंध्र मातीला गाळण क्रियेत प्राधान्य दिले जात नाही. / Porous soil is not preferred for filtration.
(c)मातीत असलेले सेंद्रिय आम्ल मातीची सुपीकता कमी करतात. / Organic acids present in soil decrease the fertility of soil.
(d)खडकळ जमिन, गाळण प्रक्रियेला आणि नॉनएरोबिक अपघटनाला उपयुक्त नाही. / Rocky soils are unsuitable for filtration and non-aerobic decomposition.
Statements (b) and (c) are incorrect because porous soil is indeed preferred for filtration, and organic acids do not necessarily decrease overall soil fertility inappropriately in all contexts.
सांडपाण्याचे वनस्पती खाद्यमध्ये रूपांतर ......... मुळे होते. / The sewage is converted into plant food by :
(a)भौतिक क्रिया / Physical action
(b)रासायनिक क्रिया / Chemical action
(c)कार्बन डायऑक्साइड / Carbon dioxide
(d)जीवाणू / Bacteria
Sewage is converted into plant food (nutrients like nitrates and phosphates) primarily through chemical actions and the action of bacteria.
सांडपाण्याच्या जीवाणू मार्फत होणाऱ्या एरोबिक अपघटनाच्या प्रक्रियेत ______ / During the aerobic decomposition of sewage, by bacteria ______
(a)आवश्यक असलेला ऑक्सिजन हा सरळ वातावरणातून घेतला जातो / the required oxygen is directly taken from the atmosphere
(b)तयार झालेल्या कार्बन डायऑक्साइडची अदलाबदल वातावरणातील ऑक्सिजन बरोबर होते / the produced carbon dioxide is interchanged with the atmospheric oxygen
(c)मातीच्या विविध थरात उपलब्ध असलेला कार्बन डायऑक्साइड वापरला जातो / the carbon dioxide present in different layers of soil is used
During aerobic decomposition by bacteria, the carbon dioxide produced is interchanged with atmospheric oxygen to sustain the biological process.
खालीलपैकी कोणती विधाने अचूक आहेत ? / The correct statements from the following are :
(a)गाळणे ही भौतिक क्रिया आहे. / Filtration is a physical action.
(b)मातीमध्ये तयार झालेल्या ऑक्सिजनची वातावरणातील कार्बन डायऑक्साइड बरोबरची अदलाबदल तापमानावर अवलंबून असते. / The interchange of oxygen produced in soil and atmospheric carbon dioxide is temperature dependent.
(c)सांडपाणी, जमिनीची सुपीकता वाढवते. / Sewage increases the fertility of soil.
(d)सेंद्रिय पदार्थाचे अपघटन हे एरोबिक किंवा नॉनएरोबिक जीवाणू द्वारे होते. / Decomposition of organic matter by bacteria could be aerobic or Non-aerobic.
Statements (a), (c), and (d) are correct: filtration is a physical process, treated sewage can add nutrients to soil increasing fertility, and organic matter decomposes via aerobic or non-aerobic bacteria.
“सर्व इसेन्शीअल तेलांची नांवें ही त्यांच्या मूळ झाडाच्या नावावरून ठेवली असतात." हे वाक्य / "All essential oils are named after their plant of origin" - This statement is
Essential oils are concentrated hydrophobic liquids containing volatile chemical compounds from plants, usually named after the plant species they are extracted from.
सुक्ष्मतुषारांचा हवामानावरील परिणाम वरीलपैकी कोणते परिणाम बरोबर आहेत ?
(a)सुर्यप्रकाशाचे थेट अवकाशात परावर्तन
(b)अप्रतक्षरित्या ढगांना प्रखर परावर्तक बनवतात
(c)सुक्ष्मतुषारांचा हवामान प्रणालीवर निव्वळ थंड परिणाम
(d)मानव निर्मित सुक्ष्म तुषारामुळे नागरिक तापमान वाढीस काही प्रमाणात आळा बसतो
Aerosols reflect sunlight directly back to space, act as cloud condensation nuclei making clouds more reflective, cause a net cooling effect on the climate system, and anthropogenic aerosols mask global warming to some extent.
🏛️ The Maharashtra angle
व्यावसायिक शीत गृहात, लोणी किती तापमानावर ठेवले जाते ? Butter is stored at what temperature, in a commercial cold storage ?
In commercial cold storage facilities, butter is stored at sub-zero temperatures around –20°C to prevent rancidity, microbial growth, and spoilage.
_____________ च्यासाहाय्याने दूरचित्रवाणीचे कार्यक्रम सर्व जगामध्ये पाठविणे शक्य आहे. TV programmes can be transmitted all over the world, with the help of ____________ .
(a)भूस्थिर उपग्रह / geostationary satellites
(b)अंतरंग तरंग प्रसारण / space wave propagation
(c)भूतरंग प्रसारण / ground wave propagation
(d)अणू तरंग / longitudinal waves
Geostationary satellites revolve at the same speed as the Earth and cover large areas, making them ideal for telecommunication and transmitting TV programs worldwide. Ground and space wave propagations have distance limitations.
पुढील शास्त्रज्ञांपैकी कोणी 1940 मध्ये प्रकाशित झालेल्या "विज्ञान व धर्म" या लेखात असे प्रतिपादन केले की "धर्म विना विज्ञान लंगडे आहे व विज्ञानाविना धर्म आंधळा आहे"? Which scientist from amongst the following in his article published in 1940 titled "Science and Religion" argued that "Science without Religion is lame and Religion without Science is blind"?
Albert Einstein famously stated in his 1940 article 'Science and Religion' that science without religion is lame and religion without science is blind.
फ्रेडरिक सेंजर (Frederick Sanger) यांना दोन वेळा रसायन शास्त्रातील नोबेल पुरस्कार देण्यात आला होता. दोन पुरस्कारां मध्ये अंतर किती होते ? / Frederick Sanger was awarded the Nobel Prize for Chemistry twice. What was the gap between the two prizes ?
Frederick Sanger was awarded the Nobel Prize in Chemistry twice, first in 1958 and second in 1980, making the gap more than 20 years.
अति लघु रेडिओतरंग भट्टीचे (2.45 GHz फ्रिक्वेन्सी) फायदे काय आहेत ? / What are the advantages of Microwave oven having microwave frequency of 2.45 GHz ?
(a)त्यामध्ये ज्वाला नाहीत / There are no flames
(b)पदार्थातील पौष्टिकता कमी प्रमाणात नष्ट होते / Destruction of nutrients is less
(c)अन्नपदार्थांमध्ये भौतिक बदल घडतो / There is a physical change in foods
(d)निर्जीनीकरण होते / Sterilization effected
Microwave ovens (2.45 GHz) operate without open flames, preserve nutrients better due to rapid heating, and effect sterilization. However, they cause chemical/structural changes rather than mere physical changes, making (c) incorrect.
खालीलपैकी कोणते विधान सत्य नाही ? Which of the following statements is not true ?
SONAR (Sound Navigation and Ranging) uses sound waves for underwater navigation and detection, whereas gold plating is an electrochemical process, making statement 4 false.