BSF Constable Science & Technology — practice questions
120 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice BSF Constable Science & Technology in the app →The Sanskrit text in which Acharya Kanada's atomic ideas are recorded is:The Greek word *atomos*, from which *atom* is derived, means:In which year did John Dalton propose his atomic theory based on scientific experiments?According to Dalton's atomic theory (1808):Who discovered the **electron** and in which year?In a cathode ray tube, the rays move from:Cathode rays are streams of:The charge of an electron, by convention, is:The actual magnitude of the charge of an electron in coulombs is approximately:J. J. Thomson received the Nobel Prize in Physics in:Thomson's model of the atom is also called the:In the watermelon analogy of Thomson's atomic model:The famous **gold foil experiment** was conducted in 1911 by:In the gold foil experiment, the particles aimed at the gold foil were:An alpha particle is identical to a nucleus of:Most alpha particles in the gold foil experiment:From the gold foil experiment, Rutherford concluded that the positive charge of an atom is:According to Rutherford's planetary model, electrons:The approximate diameter of an atom is:The approximate diameter of the nucleus is:If an atom were the size of a cricket ground (~100 m), the nucleus would be roughly the size of:Which scientific phenomenon, discovered in the late 19th century, demonstrated that atoms are NOT indivisible?J. J. Thomson worked at which famous laboratory in Cambridge?Why is Rutherford's atomic model called the **planetary model**?In Rutherford's atomic model, most of the mass of the atom is concentrated in:An atom is electrically neutral because:In Thomson's model, the colour of an atom (as shown in diagrams):The deflection of alpha particles from their straight path in the gold foil experiment is technically called:Consider the following pairs:
<table><tr><th>Plant</th><th>Description</th></tr><tr><td>I. Cassava</td><td>WooConsider the following types of vehicles :
I. Full battery electric vehicles
II. Hydrogen fuel cell vehicles
IWith reference to Unmanned Aerial Vehicles (UAVs), consider the following statements:
I. All types of UAVs canIn the context of electric vehicle batteries, consider the following elements:
I. Cobalt
II. Graphite
III. LitConsider the following substances:
I. Ethanol
II. Nitroglycerine
III. Urea
Coal gasification technology can beWhat is the common characteristic of the chemical substances generally known as CL-20, HMX and LLM-105, which Consider the following statements :
I. It is expected that Majorana 1 chip will enable quantum computing.
II. With reference to monoclonal antibodies, often mentioned in news, consider the following statements:
I. They aConsider the following statements :
Statement I :
Some rare earth elements are used in the manufacture of flatConsider the following statements :
I. Indian Railways have prepared a National Rail Plan (NRP) to create a 'fConsider the following space missions :
I. Axiom-4
II. SpaDeX
III. Gaganyaan
How many of the space missions giWith reference to India's defence, consider the following pairs :
<table><tr><th>Aircraft type</th><th>DescripGPS-Aided Geo Augmented Navigation (GAGAN) uses a system of ground stations to provide necessary augmentation.Consider the following plants:
1. Groundnut
2. Horse-gram
3. Soybean
How many of the above belong to the pea fThe organisms "Cicada, Froghopper and Pond skater" are :With reference to radioisotope thermoelectric generators (RTGs), consider the following statements:
1. RTGs arConsider the following statements:
Statement-I:
Giant stars live much longer than dwarf stars.
Statement-II:
CWhich one of the following is synthesised in human body that dilates blood vessels and increases blood flow?Consider the following activities:
1. Identification of narcotics on passengers at airports or in aircraft
2. Consider the following aircraft:
1. Rafael
2. MiG-29
3. Tejas MK-1
How many of the above are considered fifth In which of the following are hydrogels used ?
1. Controlled drug delivery in patients
2. Mobile air-condition“Membrane Bioreactors” are often discussed in the context of :Which one of the following words/phrases is most appropriately used to denote "an interoperable network of 3D Which of the following organisms perform waggle dance for others of their kin to indicate the direction and thConsider the following statements:
1. Some mushrooms have medicinal properties.
2. Some mushrooms have psychoaConsider the following statements :
1. Some microorganisms can grow in environments with temperature above theConsider the following actions:
1. Detection of car crash/collision which results in the deployment of airbagsConsider the following pairs :
<table><tr><th>Objects in space</th><th>Description</th></tr><tr><td>1. CepheidWhich one of the following countries has its own Satellite Navigation System?Consider the following statements :
1. Ballistic missiles are jet-propelled at subsonic speeds throughout theiWith reference to green hydrogen, consider the following statements :
1. It can be used directly as a fuel for'Wolbachia method' is sometimes talked about with reference to which one of the following?With reference to India, consider the following statements:
1. Monazite is a source of rare earths.
2. MonazitConsider the following:
1. Aarogya Setu
2. CoWIN
3. DigiLocker
4. DIKSHA
Which of the above are built on top oWith reference to Web 3·0, consider the following statements:
1. Web 3·0 technology enables people to control With reference to "Software as a Service (SaaS)", consider the following statements:
1. SaaS buyers can customWhich one of the following statements best reflects the idea behind the "Fractional Orbital Bombardment SystemWhich one of the following is the context in which the term "qubit" is mentioned?Consider the following statements:
1. Biofilms can form on medical implants within human tissues.
2. Biofilms Consider the following statements in respect of probiotics:
1. Probiotics are made of both bacteria and yeast.In the context of vaccines manufactured to prevent COVID-19 pandemic, consider the following statements:
1. ThConsider the following statements:
1. Other than those made by humans, nanoparticles do not exist in nature.
2With reference to recent developments regarding 'Recombinant Vector Vaccines', consider the following statemenIn the context of hereditary diseases, consider the following statements:
1. Passing on mitochondrial diseasesBollgard I and Bollgard II technologies are mentioned in the context ofIn a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following?
Consider the following:
1. Bacteria
2. Fungi
3. Virus
Which of the above can be cultured in artificial/synthetConsider the following statements:
1. Adenoviruses have single-stranded DNA genomes whereas retroviruses have Water can dissolve more substances than any other liquid becauseWith reference to street-lighting, how do sodium lamps differ from LED lamps?
1. Sodium lamps produce light inBisphenol A (BPA), a cause of concern, is a structural/key component in the manufacture of which of the followWhich one of the following is a reason why astronomical distances are measured in light-years?In the context of recent advances in human reproductive technology, “Pronuclear Transfer” is used forWith reference to Visible Light Communication (VLC) technology, which of the following statements are correct?With reference to “Blockchain Technology”, consider the following statements:
1. It is a public ledger that evConsider the following activities:
1. Spraying pesticides on a crop field
2. Inspecting the craters of active "The experiment will employ a trio of spacecraft flying in formation in the shape of an equilateral triangle tConsider the following statements:
1. Genetic changes can be introduced in the cells that produce eggs or sperWhat is the importance of using Pneumococcal Conjugate Vaccines in India?
1. These vaccines are effective agaiIn India, the term "Public Key Infrastructure" is used in the context ofWhich of the following statements are correct regarding the general difference between plant and animal cells?In India, why are some nuclear reactors kept under "IAEA Safeguards" while others are not?With reference to communication technologies, what is/are the difference/differences between LTE (Long-Term EvIn the context of digital technologies for entertainment, consider the following statements:
1. In Augmented RConsider the following statements:
A digital signature is
1. an electronic record that identifies the certifyiIn the context of wearable technology, which of the following tasks is/are accomplished by wearable devices?
1'RNA interference (RNAi)' technology has gained popularity in the last few years. Why?
1. It is used in develoRecently, scientists observed the merger of giant 'blackholes' billions of light-years away from the Earth. WhWhich of the following are the reasons for the occurrence of multi-drug resistance in microbial pathogens in IWhat is Cas9 protein that is often mentioned in news?Which one of the following statements is not correct?What is/are the consequence/consequences of a country becoming the member of the ‘Nuclear Suppliers Group’?
1.The identity platform ‘Aadhaar’ provides open “Application Programming Interfaces (APIs)”. What does it imply?In the Indian context, what is the implication of ratifying the ‘Additional Protocol’ with the ‘International What is "Terminal High Altitude Area Defense (THAAD)", sometimes seen in the news?In which of the following areas can GPS technology be used?
1. Mobile phone operations
2. Banking operations
3The terms 'WannaCry, Petya and EternalBlue' sometimes mentioned in the news recently are related toWith reference to the Indian Regional Navigation Satellite System (IRNSS), consider the following statements:
Consider the following phenomena:
1. Light is affected by gravity.
2. The Universe is constantly expanding.
3.Consider the following pairs:
<table><tr><th>Terms sometimes seen in news</th><th>Context / Topic</th></tr><tr"3D printing" has applications in which of the following?
1. Preparation of confectionery items
2. ManufactureWith reference to India's satellite launch vehicles, consider the following statements:
1. PSLVs launch the saWhich of the following statements is/are correct regarding Smart India Hackathon 2017?
1. It is a centrally spWhich of the following are the objectives of 'National Nutrition Mission'?
1. To create awareness relating to Consider the following statements :
1. The Nuclear Security Summits are periodically held under the aegis of tConsider the following statements:
1. In tropical regions, Zika virus disease is transmitted by the same mosquOrganic Light Emitting Diodes (OLEDs) are used to create digital display in many devices. What are the advantaWhat is the application of Somatic Cell Nuclear Transfer Technology?In India, it is legally mandatory for which of the following to report on cyber security incidents?
1. ServiceWhat is the purpose of ‘evolved Laser Interferometer Space Antenna (eLISA)’ project?With reference to 'LiFi', recently in the news, which of the following statements is/are correct?
1. It uses lIn the context of the developments in Bioinformatics, the term 'transcriptome', sometimes seen in the news, re