Daily Static MCQs for UPSC & State PSC Exams - Science and Technology (16 June 2023)

Daily Static MCQs Quiz for UPSC, IAS, UPPSC/UPPCS, MPPSC. BPSC, RPSC & All State PSC Exams

Subject : Science and Technology

1. Consider the following statement with reference to carbon nanotubes:

1. Carbon nanotubes are biodegradable.
2. They can be used in biochemical sensors.
3. They can be used as carriers of drugs and antigens in the human body.

Which of the statements given above are correct?

(a) Only one
(b) Only two
(c) All three
(d) None

Answer: (B)

Explanation:

  • Carbon nanotubes are generally considered to be non-biodegradable. They are highly stable and resistant to degradation by biological processes. This is one of the challenges in their environmental impact and long-term persistence. Hence, statement 1 is incorrect.
  • Carbon nanotubes possess unique electrical and mechanical properties that make them well-suited for use in biochemical sensors. These properties include: electrical conductivity, high surface area, chemical sensitivity, mechanical strength, etc. Hence, statement 2 is correct.
  • Carbon nanotubes have been studied for their potential use as carriers or delivery vehicles for drugs and antigens in the human body. Hence, statement 3 is correct.

Hence, option (b) is the correct answer.

2. With reference to ‘Li-Fi’, consider the following statements:

1. It is a wireless technology and is several times faster than ‘WiFi’.
2. It uses light as the medium for high-speed data transmission.

Select the correct answer using the code given below.

(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Answer: (C)

Explanation:

  • Li-Fi or Light Fidelity, is a wireless communication technology that utilizes visible light or infrared signals to transmit data wirelessly. Compared to traditional Wi-Fi, Li-Fi can achieve significantly higher data transfer rates. Hence, statement 1 is correct.
  • Li-Fi employs light as the medium for data transmission. It uses light-emitting diodes (LEDs) to emit light signals that carry the data, and specialized photodetectors receive and interpret these signals, enabling high-speed data communication. Hence, statement 2 is correct.

Hence, option (c) is the correct answer.

3. Consider the following pairs:

1. Chinese fast food – Monosodium glutamate
2. Lipstick – Lead
3. Soft drinks – Brominated vegetable oils

How many of the pairs are correctly matched?

(a) Only one pair
(b) Only two pairs
(c) All three pairs
(d) None of the pairs

Answer: (B)

Explanation:

  • Monosodium glutamate (MSG) is a flavor enhancer commonly used in Chinese fast food and various other cuisines. Hence, pair 1 is correctly matched.
  • Some lipsticks have been found to contain trace amounts of lead, although the use of lead in lipsticks has significantly decreased over time. Hence, pair 2 is correctly matched.
  • Soft drinks do not typically contain brominated vegetable oils (BVO). BVO is sometimes used in citrus-flavored soft drinks, but its usage has been decreasing due to safety concerns. Hence, pair 3 is not correctly matched.

Hence, option (b) is correctly matched.

4. With reference to ‘fuel cells’, consider the following statements :

1. If pure hydrogen is used as a fuel, the fuel cell emits heat and water as by-products.
2. Fuel cells produce electricity in the form of Alternating Current (AC).
3. Fuel cells can be used for powering buildings and not for small devices like laptop computers.

How many of the statements given above are correct?

(a) Only one
(b) Only two
(c) All three
(d) None

Answer: (A)

Explanation:

  • When pure hydrogen is used as a fuel in a fuel cell, the chemical reaction between hydrogen and oxygen produces electricity, heat, and water as by-products. This is one of the advantages of fuel cells, as the only by-product is water, making them a clean and environmentally friendly energy source. Hence, statement 1 is correct.
  • Fuel cells produce electricity in the form of Direct Current (DC), not Alternating Current (AC). The generated electricity from a fuel cell is in the form of a continuous flow of electrons in one direction. Hence, statement 2 is incorrect.
  • Fuel cells can be used for a wide range of applications, including powering buildings, vehicles, portable devices, and even small devices like laptop computers. Fuel cell technology has been advancing, and there are various types and sizes of fuel cells designed for different applications. Hence, statement 3 is incorrect.

Hence, option (a) is the correct answer.

5. Consider the following diseases:

1. Smallpox
2. Diphtheria
3. Chickenpox

Which of the above diseases has/have been eradicated in India?

(a) Only one
(b) Only two
(c) All three
(d) None

Answer: (A)

Explanation:

  • Smallpox is the only disease among the three listed that has been eradicated in India. Smallpox was officially declared eradicated worldwide in 1980, following a successful global vaccination campaign led by the World Health Organization (WHO). India was one of the countries that achieved smallpox eradication.
  • Diphtheria and chickenpox have not been eradicated in India. Diphtheria is a bacterial infection that can cause severe respiratory problems and other complications. Chickenpox, caused by the varicella-zoster virus, is a highly contagious viral infection characterized by itchy skin rashes.

Hence, option (a) is the correct answer.