Question Discussion & Solution

The correct answer is Rakesh Sharma.

Key Points

• Rakesh Sharma is the first Indian to enter space.
  • He was selected as a cosmonaut for a joint Soviet-Indian spaceflight in 1982.
  • He made history by becoming the first Indian to travel to space in 1984.
  • He flew on Soyuz T-11 with commander Yury Malyshev and flight engineer Gennady Strekalov, to the space station Salyut 7 on 3^rd April 1984.
  • Rakesh Sharma and his crewmates landed in Kazakhstan on 11^th April 1987 after the successful completion of the mission.
  • He is the only Indian citizen to travel in space.

Additional Information

• Kalpana Chawla was the first Indian-origin woman to enter space.
  • She was killed in the space shuttle Columbia disaster on 1st February 2003.
• Sunita Williams is the second Indian-origin woman to enter space.
  • The first marathon in space was run by Sunita Williams.
• Yuri Gagarin is the first man to enter space.
• Ravish Malhotra was an Air Force test pilot in India. 
  • He served as a backup for Rakesh Sharma on the Soyuz T-11 mission.

In this Devotion is something different then living being. 

Hence, "Devotion" is the correct answer.

• The Best example of Run time polymorphism is Function Overriding
• Function Overloading is the example of Compile time polymorphism
• Protected is an Access modifier  

Important Point

Compile-time polymorphism

It means binding is occurring at compile time It can be achieved through static binding. If a class has multiple methods having the same name but different in parameters, it is known as Method Overloading.

Run time polymorphism

At run time we came to know which method is going to invoke It can be achieved through dynamic binding. If subclass (child class) has the same method as declared in the parent class, it is known as method overriding

Access Modifiers

It specifies the accessibility or scope of a field, method, constructor, or class. There are three types of Access modifiers

• Public: The methods or data members that are declared as public can be accessed anywhere in the program.
• Private:  The methods or data members declared as private are accessible only within the class in which they are declared.
• Protected: The methods or data members declared as protected can accessible within the same class or class which is inherited from it.

In the question figure, there are 2 square blocks. Half of both square blocks are shaded and the other half is blank. One of the square blocks has its left half shaded and another square block has its right half shaded. Thus, in the answer figure, the square block whose left half is shaded should have its right block shaded and the square block whose right half is shaded should have its left half shaded.

Therefore option 1, 2, and 4 gets eliminated.

Hence, the figure in option 3 is the correct answer.

CONCEPT:

Rutherford’s Model of the Atom:

• He bombarded the beam of alpha particles on a very thin gold foil.
• While bombarding he observes the number of scattering of particles –
  • Most of the particles passed either un-deviated or with a very small deviation.
  • Some deviated by large angles
  • 1 out of 8000 was deflected by more than 90°
• The conclusion to this deflection:
  • Most of the space of an atom is empty.
  • At the centre of an atom having a tiny positively charged particle called a nucleus.
  • The centre nucleus has all the mass of an atom.
  • The amount of positive charge at the nucleus is equal to the total amount of negative charges on all the electrons of the atom.
  • All the electrons revolve around the nucleus and coulomb force provide the centripetal force

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EXPLANATION:

• After the α -particles scattering experiment, the following conclusions were made by Rutherford as regard as atomic structure:

• Most of the mass (at least 99.95%) and all of the charge of an atom concentrated in a very small region is called the atomic nucleus. Therefore option 4 is correct.
• The nucleus consists of proton and neutron, in which proton was first discovered by Rutherford but neutrons were later discovered by James Chadwick in 1932.
• In an atom, there is maximum empty space and the electrons revolve around the nucleus in the same way as the planets revolve around the sun and the nnumber of protons and electrons inside an atom are equal under normal conditions (non-ionized).