Question Discussion & Solution

• Multiple Inheritance in C++ is one in which a class can inherit members from more than one class
• A class who inherit the property is derived class and class from whom it is inherited is base class or parent class

Example:

class X //base class

{

public:

 X() { cout << "X's constructor" ; }

};

 class Y //base class

{

public:

 Y() { cout << "Y's constructor "; }

};

 class C: public B, public A // Derived class: Multiple inheritance

{

public:

 Z() { cout << "Z's constructor" ; }

The correct answer is Fossil fuels.

Key Points

Non-Renewable Resources Examples

• Fossil Fuel
• Coal
• Rare earth elements
• Petroleum products
• Uranium

Thus, Fossil fuels are a non-renewable source of energy.

Additional Information 

Types of Renewable Energy

Solar Energy:

• ​The radiant light and heat energy from the sun is harnessed with the use of solar collectors.
• These solar collectors are of various types such as photovoltaics, concentrator photovoltaics, solar heating, (CSP) concentrated solar power, artificial photosynthesis, and solar architecture.
• This collected solar energy is then used to provide light, heat, and different other forms of electricity.

Wind Energy:

• The energy we get from winds is known as wind energy.
• For this, windmills have been used for hundreds of years to pump out water from the ground. We use large tall wind turbines that allow winds to generate electricity.
• The natural airflow on the surface of the earth is used to run the wind turbines.
• The most preferred locations for these wind turbines to be installed are the areas which and strong and have constant airflows on offshore and sites that are at high altitudes.

Hydroelectricity:

• According to statistics, hydroelectricity generated around 16.6% of the global energy resources and constituted about 70% of all the renewable electricity.
• This energy is another alternative source of energy that is generated by the construction of dams and reservoirs on the flowing water, the kinetic energy from the flowing water is used to run the turbines which generate electricity.
• Tidal power converts the energy of tides and Wave power which captures the energy from the surface of the ocean waves for power generation.
• These two forms of hydropower also have huge potential in electric power generation

Geothermal Energy:

• It is the energy that is generated from the thermal energy which is stored in the earth.
• The heat energy is captured on sources such as hot springs and volcanoes and this heat is directly used by industries for heating the water and other purposes.

Bio-Energy:

• This type of energy is derived from biomass which is a type of biological material derived from living organisms and plant-derived materials which are called lignocellulosic biomass.
• Biomass can be directly used via combustion to produce heat and indirectly it can be used to convert to biofuels.
• Biomass can be converted to other usable forms of energy such as transportation fuels like ethanol, biodiesel, and methane gas.

The correct answer is Bhup Singh.

• Bhup Singh was the real name of freedom fighter Vijay Singh Pathik.

​Key Points

• Vijay Singh Pathik
  • ​Vijay Singh Pathik, popularly known as Rashtriya Pathik, was an Indian revolutionary.
  • His real name was Bhup Singh.
  • He was among the first Indian revolutionaries who lit the torch of the freedom movement against British rule.
  • Much before Mohandas K. Gandhi initiated the Satyagrah movement, Pathik experimented during the Bijolia’s Kisan agitation.

Additional Information

• Being Indian Revolutionary and Satyagrahi, he was also a very well known Hindi poet, writer and journalist.
• He was the editor of Rajasthan Kesari and Naveen Rajasthan.
• He also started his own independent Hindi weekly, the Rajasthan Sandesh and the Nav Sandesh from Ajmer.

CONCEPT:

• Ultrasonic waves are the sound waves with frequencies higher than the upper audible limit of human hearing.
  • They have a short wavelength.
• Echo: If we shout or clap near a suitable reflecting object such as a tall building or a mountain, we will hear the same sound again a little later. This sound which we hear is called an echo.
  • Echoes are heard due to the phenomenon of Reflection of sound waves.
• SONAR: It a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water
  • SONAR stands for ‘Sound Navigation and Ranging.’
  • SONAR is based on the principle of echo.
  • Sonar is often used as a measurement of acoustic location and echo characteristics of the target object in the water.
  • It sends ultrasonic waves towards the bottom area of the sea and after reflection, the sound comes to the ship. We measure the time taken by the sound wave and then we get the depth. 

EXPLANATION:​

• From the above discussion, we can say that the SONAR uses the principle of reflection of sound waves(Echo) to detect and locate objects. So option 2 is correct.
• Reverberation: The persistence of sound in a closed enclosure, due to continuous reflections at the walls or the floor or the ceiling of the enclosure, even after the source has stopped producing sound is known as 'reverberation'.

The correct answer is 1939.

Key Points

Congress Party: 

• An Indian political party founded in 1885 as Indian National Congress.
• Founded by Allen Hume, a British colonist and, until World War-I it was a moderate body.
• Later, under the leadership of Mahatma Gandhi, it began a campaign of non-violent non-cooperation.
• It was declared illegal between 1932-34. It led the movement to end British rule and was the government party after independence from 1947-77.

Key people-Congress Party Leader: 

•  Maulana Abul Kalam Azad (1888-1958): Leading Muslim member of Congress Party; Congress president, 1940-1946; Indian education minister after independence.
•  Mohandas Karamchand Gandhi (Mahatma) (1869-1948):  Studied law in London; 1893-1914, worked in South Africa; on return to South Africa, rose to dominance in Congress Party, becoming its president in 1924. Led a number of civil disobedience campaigns, spending a number of spells in prison. Made numerous attempts between 1944-1947 to stop the partition of India but failed. Assassinated, 1948.
• Jawaharlal (Pandit) Nehru(1889-1964) Barrister and politician in the United Provinces of India; supporter of Gandhi; President of Indian National Congress, 1929, 1936-37, 1946, 1951-54; first prime minister of India, 1947-1964.