[Mission 2023] STATIC QUIZ, 5 April 2023 – Science and Technology

Solution: a)

Distributed ledger technology (DLT) and Block Chain technology:

• Distributed ledger technology (DLT) is a digital system for recording the transaction of assets in which the transactions and their details are recorded in multiple places at the same time.
• Unlike traditional databases, distributed ledgers have no central data store or administration functionality.
• Whether distributed ledger technologies, such as blockchain, will revolutionize how governments, institutions and industries work is an open question.
• Blockchain technology is a specific kind of DLT that came to prominence after Bitcoin, a cryptocurrency that used it, became popular.
• Cryptocurrencies such as Bitcoin use codes to encrypt transactions and stack them up in blocks, creating Blockchains. It is the use of codes that differentiates cryptocurrencies from other virtual currencies.

Solution: a)

The idea of an object in space so massive and dense that light could not escape it has been around for centuries. Most famously, black holes were predicted by Einstein’s theory of general relativity, which showed that when a massive star dies, it leaves behind a small, dense remnant core.

Scientists can’t directly observe black holes with telescopes that detect x-rays, light, or other forms of electromagnetic radiation. We can, however, infer the presence of black holes and study them by detecting their effect on other matter nearby. If a black hole passes through a cloud of interstellar matter, for example, it will draw matter inward in a process known as accretion. A similar process can occur if a normal star passes close to a black hole. In this case, the black hole can tear the star apart as it pulls it toward itself. As the attracted matter accelerates and heats up, it emits x-rays that radiate into space. Recent discoveries offer some tantalizing evidence that black holes have a dramatic influence on the neighborhoods around them – emitting powerful gamma ray bursts, devouring nearby stars, and spurring the growth of new stars in some areas while stalling it in others.

Most black holes form from the remnants of a large star that dies in a supernova explosion. 

Solution: c)

Most of the communication satellites today are placed in a geostationary orbit.

Geostationary satellites in orbits circle the Earth at the same rate as the Earth spins.

• The Earth takes nearly 24 hours to make one full revolution around the earth allowing them to observe a location constantly on earth since earth too rotates at the same speed. So based on Kepler’s Laws of Planetary Motion, this would put the satellite at approximately 35,790 km above the Earth.
• The satellites are located near the equator since at this latitude there is a constant force of gravity from all directions. At other latitudes, the bulge at the centre of the Earth would pull the satellite down.

Solution: d)

NFT is a one-of-its-kind asset that is not interchangeable in nature. It means that the NFT is not replaceable by another ‘identical’ item.

For example, if two individuals hold a bitcoin each, they can exchange their bitcoins, which are a replica of each other and have the same value. However, NFTs are not interchangeable, as they are more like pieces of art where each and every token is unique in itself. While bitcoins are also digital assets, NFTs are unique digital assets with each token representing a unique value.

NFTs have evolved to include digital real estate, video game items, digital art and music.

Solution: c)

Wireless charging works by transferring energy from the charger to a receiver in the back of the phone via electromagnetic induction.

The charger uses an induction coil to create an alternating electromagnetic field, which the receiver coil in the phone converts back into electricity, to be fed into the battery.