Question Discussion & Solution

The correct answer is Atomic Energy.

Key Points

• A biomass energy source is one that is derived from organic matter.
• The source of atomic energy is radioactive metals which are of non-organic nature and thus cannot be classified as a biomass energy source.

Important Points

Email bomb

It is an attack on your inbox that involves sending massive amounts of emails to your address. Sometimes these messages are complete gibberish, but more often they’ll be confirmation emails for newsletters and subscriptions.

Additional Information

Spoofing 

It is the act of disguising a communication from an unknown source as being from a known, trusted source. Spoofing can apply to emails, phone calls, and websites, or can be more technical, such as a computer spoofing an IP address, Address Resolution Protocol (ARP), or Domain Name System (DNS) server.

Smurf Attack

It is a form of a DDoS attack that causes packet flood on the victim by exploiting/abusing ICMP protocol. When deployed, large packets are created using a technique called “spoofing”. The phony source address that is now attached to these packets becomes the victim, as their IP is flooded with traffic. The small ICMP packet generated by the tool causes big trouble for a victim, hence the name Smurf.

Ping storm

It is a condition in which the Internet ping program is used to send a flood of packets to a server to  test its ability to handle a high amount of traffic or, maliciously, to make the server inoperable

Hence Option 1 is correct

Concept:

• Atoms are made up of subatomic particles - electrons protons and neutrons.
• In the center of an atom, a nucleus is present which contains protons and neutrons together known as nucleons.
• The mass of an atom is most concentrated at the center of the atom, i.e. the nucleus.

​Electrons:

• Discovered by Sir J.J Thomson in the year 1897.
• Previously named as cathode rays as they were supposed to be emitted from the cathode.
• They are deflected towards the positive side.
• They have high kinetic energy.
• They are deflected by an electric and magnetic field.
• It has a negative charge of

  \(charge=1.602\times10^{-19} coulombs \)
\(mass={1\over 1837}\times 9.107\times 10^{-28}g\)

Protons:

• Discovered by Goldstein.
• Depicted first as positive rays because it seemed to emerge from the anode.
• Mass of a proton is

 \(1.670 \times 10^{- 24}g\)

\(Charge=1.602\times 10^{-19} coulombs\)​

Explanation:

• Rutherford's discovery led to the discovery of nucleus.
• He found out that most of the mass of the nucleus is situated in its centre and contains the positively charged particles protons.
• The atom is otherwise empty and as electrons have negligible mass, the mass of an atom should be equal to the sum of mass of protons present in it.
• However, it was seen that in Helium, there are only two protons, so its mass should be twice the mass of each proton = \(2\times 1.008 a.m.u\).
• Experimental results revealed that it has a mass of 4.003a.m.u.
• Hence, it was concluded that the nucleus has particles containing no charge but mass almost equal to that of a proton.
• This was established by scientist James chadwick in 1932.

Additional Information

Rutherford's gold foil experiment: 

• He discovered the atomic nucleus and gave us an atomic model.
• He directed alpha particles towards a metal sheet.
• He saw that most of the alpha particles, which are positively charged particles, are not getting deflected.
• Most of the alpha particles emerged undeflected.

• Therefore, he concluded that most of the mass of the nucleus is situated in its centre and contains the positively charged particles protons.
• Electrons revolve around the nucleus in certain orbits.

The correct answer is PM Narendra Modi.

Key Points

• Prime Minister Narendra Modi will host the first India-Central Asia Summit in a virtual format on 27 January 2022.
• This will be the first engagement of its kind between India and the Central Asian countries at the level of leaders.
• The virtual summit will see the participation of the five countries Kazakhstan, Uzbekistan, Tajikistan, Turkmenistan, and the Kyrgyz Republic.

Additional Information

• Prime Minister Narendra Modi addressed the World Economic Forum's (WEF) Davos Agenda virtual event on 17 Jan'22.
• PM Narendra Modi has been invited as the chief guest at the 54th convocation ceremony of the IIT Kanpur on 28th Dec 2021.
• Amid the Omicron scare, Prime Minister Narendra Modi has announced the Covid-19 vaccine for children and booster doses for Health workers and senior citizens in December 2021.
• Prime Minister Narendra Modi has laid the foundation stone of Ganga Expressway in Shahjahanpur, Uttar Pradesh in December 2021.
• In October 2021, Prime Minister Narendra Modi has launched the Indian Space Association (ISA).
• Prime Minister Narendra Modi has been named among the 100 most influential people of 2021 by Time Magazine.
• In August 2021, Narendra Modi has become the first Indian Prime Minister to chair an open debate at United Nations Security Council (UNSC).

• For most computer languages, the name of the file that holds the source code to a program is immaterial
• However, in Java the name given to a source file is very important
• The Java compiler requires that a source file uses the .java filename extension
• Only file.java follow the properties in the given options
• In Java, a source file is officially called a compilation unit; It is a text file that contains one or more class definitions