31
Question 31
With reference to radioisotope thermoelectric
generators (RTGs), consider the following
statements:
1. RTGs are miniature fission reactors.
2. RTGs are used for powering the onboard systems of spacecrafts.
3. RTGs can use Plutonium-238, which is a by-product of weapons development.
Which of the statements given above are correct?
1. RTGs are miniature fission reactors.
2. RTGs are used for powering the onboard systems of spacecrafts.
3. RTGs can use Plutonium-238, which is a by-product of weapons development.
Which of the statements given above are correct?
AOptions
A
A) 1 and 2 only
B
B) 2 and 3 only
C
C) 1 and 3 only
D
D) 1, 2 and 3
BSolution
Let's analyze each statement regarding Radioisotope Thermoelectric Generators (RTGs):
1. Statement 1 is incorrect. RTGs are *not* miniature fission reactors. Fission reactors generate power through controlled nuclear chain reactions. RTGs, on the other hand, produce electricity by converting the heat generated from the *radioactive decay* of a suitable radioactive material (like Plutonium-238) into electricity using thermocouples. There is no controlled chain reaction involved.
2. Statement 2 is correct. RTGs are indeed widely used to power spacecraft, particularly those operating in deep space where solar power is insufficient (e.g., Voyager, Cassini, Perseverance rover). They provide a reliable, long-lasting power source for onboard systems, instruments, and communications.
3. Statement 3 is correct. RTGs typically use Plutonium-238 (²³⁸Pu) as their heat source. Plutonium-238 is a specific isotope of plutonium, which is *not* fissile and therefore not directly used in nuclear weapons (weapons primarily use Plutonium-239). However, ²³⁸Pu can be produced in nuclear reactors by irradiating Neptunium-237. The production of plutonium isotopes, in general, is related to nuclear programs, including those for weapons development or nuclear power, and thus ²³⁸Pu can be considered a by-product or associated with such programs, though it's distinct from weapons-grade material itself. The U.S., for instance, has restarted production of Pu-238 at national laboratories for RTG needs, using processes related to nuclear material handling.
Therefore, statements 2 and 3 are correct.
1. Statement 1 is incorrect. RTGs are *not* miniature fission reactors. Fission reactors generate power through controlled nuclear chain reactions. RTGs, on the other hand, produce electricity by converting the heat generated from the *radioactive decay* of a suitable radioactive material (like Plutonium-238) into electricity using thermocouples. There is no controlled chain reaction involved.
2. Statement 2 is correct. RTGs are indeed widely used to power spacecraft, particularly those operating in deep space where solar power is insufficient (e.g., Voyager, Cassini, Perseverance rover). They provide a reliable, long-lasting power source for onboard systems, instruments, and communications.
3. Statement 3 is correct. RTGs typically use Plutonium-238 (²³⁸Pu) as their heat source. Plutonium-238 is a specific isotope of plutonium, which is *not* fissile and therefore not directly used in nuclear weapons (weapons primarily use Plutonium-239). However, ²³⁸Pu can be produced in nuclear reactors by irradiating Neptunium-237. The production of plutonium isotopes, in general, is related to nuclear programs, including those for weapons development or nuclear power, and thus ²³⁸Pu can be considered a by-product or associated with such programs, though it's distinct from weapons-grade material itself. The U.S., for instance, has restarted production of Pu-238 at national laboratories for RTG needs, using processes related to nuclear material handling.
Therefore, statements 2 and 3 are correct.
CStrategy
For questions on nuclear technology, distinguish between different energy generation mechanisms (fission, decay). Understand the specific isotopes used for different applications (e.g., Pu-238 for RTGs vs. Pu-239 for weapons). Always check the exact nature of 'by-product' or 'related to'.
DSyllabus Analysis
Science & Technology: Nuclear Technology (Radioisotopes, Energy Generation), Space Technology (Spacecraft Power Systems).
EQuestion Analysis
This is a factual and conceptual question from Science & Technology, specifically on nuclear and space technology. The key distinction is between fission reactors and radioisotope decay. The nature of Plutonium-238 and its relation to weapons programs can be nuanced but is generally considered correct in this context. Medium difficulty.