17 September 2024

Q1. Consider the following statements regarding Quasars:

• Quasars are very luminous objects in faraway galaxies.
• They are not found in galaxies that have supermassive blackholes.

Which of the above statements is/are correct:

1. 1 only
2. 2 only
3. Both 1 and 2
4. Neither 1 nor 2

Solution:

(A)

• An international team of astronomers have discovered the most distant ‘radio-loud’ quasar with the help of European Southern Observatory’s Very Large Telescope (ESO’s VLT).
• It took 13 billion years for the quasar’s light to reach earth, according to a paper published in The Astrophysical Journal March 8, 2021.
• Quasars are very luminous objects in faraway galaxies that emit jets at radio frequencies.
• They are only found in galaxies that have supermassive blackholes which power these bright discs.
• However, 90 per cent of them do not emit strong radio waves, making this newly-discovered one special.
• Most active galaxies have a supermassive black hole at the centre which sucks in surrounding objects.
• Quasars are formed by the energy emitted by materials spiralling around a blackhole right before being sucked into it.

Q2. TrueNat mchines, recently seen in news can be used to test:

• Covid-19
• Tuberculosis
• HIV

Select the correct answer code:

1. 1 only
2. 1, 2
3. 1, 3
4. 1, 2, 3

Solution:

(D)

• TrueNat This is a privately designed test that works on the same principle as RT-PCR, but with a smaller kit and with faster results.
• TrueNat, designed by MolBio Diagnostics Pvt Ltd, Goa, is commonly used for tuberculosis and HIV testing.
• The ICMR approved TrueNat for screening and confirmation for Covid-19.

Q3. Which of the following services generally use encryption to secure data transmission:

• Payment gateways
• Messaging services
• Wireless microphones and Bluetooth devices

Select the correct answer code:

1. 1, 2
2. 1, 2, 3
3. 1, 3
4. 2, 3

Solution:

(B)

• Encryption is the process of encoding messages or information in such a way that only authorized parties can read it.
• For example: word “ABC” can become “BCD” in encrypted form, if every letter is replaced by next alphabet.
• Those who know how it is encoded can only able to read “ABC” correctly.
• All messaging services like WhatsApp, Viber, Google Chat, Yahoo messenger use encrypted services. Banks (payment gateways) and e-commerce sites also use encryption to protect financial and private data including passwords.
• Encryption is also used to protect data in transit, for example data being transferred via networks (e.g. the Internet, e-commerce), mobile telephones, wireless microphones, wireless intercom systems, Bluetooth devices and bank automatic teller machines.

Q4. Which of the following is/are examples of natural nanomaterials, i.e. those which occur naturally in the world:

• Haemoglobin in our blood
• Particles in volcanic ash
• Nano-structures that give colour to peacock’s feathers
• Exhaust from fossil fuel burning engines

Select the correct answer code:

1. 2, 3, 4
2. 1, 2, 3, 4
3. 1, 2, 3
4. 1, 2

Solution:

(C)

• Natural nanomaterials, as the name suggests, are those that occur naturally in the world.
• These include particles that make up volcanic ash, smoke, and even some molecules in our bodies, such as the hemoglobin in our blood.
• The brilliant colors of a peacock’s feathers are the result of spacing between nanometer-scale structures on their surface.
• Man-made nanomaterials are those that occur from objects or processes created by people.
• Examples include exhaust from fossil fuel burning engines and some forms of pollution

Q5. The commercial applications of nano-technology in agriculture sector include:

• Delivery of pesticides and fertilizers
• Monitoring soil conditions and plant growth
• Detection of animal and plant pathogens
• Deliver DNA to plants

Select the correct answer code:

1. 1, 2, 3
2. 1, 2
3. 1, 2, 3, 4
4. 1, 2, 4

Solution:

(C)