Question Discussion & Solution

The correct answer is Solar cells.

Key Points

• A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect.
• Photovoltaic cells consist of two or more layers of semiconductors with one layer containing positive charge and the other negative charge lined adjacent to each other.
• Sunlight, consisting of small packets of energy termed as photons, strikes the cell, where it is either reflected, transmitted or absorbed.
• When the photons are absorbed by the negative layer of the photovoltaic cell, the energy of the photon gets transferred to an electron in an atom of the cell.
• With the increase in energy, the electron escapes the outer shell of the atom.
• The freed electron naturally migrates to the positive layer creating a potential difference between the positive and the negative layer.
• When the two layers are connected to an external circuit, the electron flows through the circuit, creating a current.
• Advantages of Photovoltaic Cells:
  • ​Environmental Sustainability
  • Economically Viable
  • Accessible
  • Renewable
• Disadvantages of Photovoltaic Cells:
  • ​The efficiency of solar panels is low compared to other renewable sources of energy.
  • Power generated gets reduced during cloudy weather.
  • Long-range transmission of solar energy is inefficient and difficult to carry.
  • Photovoltaic panels are fragile and can be damaged relatively easily.

The correct answer is Pooja Kadian.

• Pooja Kadian was the first Indian to receive the title of world champion in Wushu in 2017.

Key Points

• Pooja Kadian won the gold in women’s 75kg category.
• Pooja defeated Evgeniya Stepanova of Russia in the final.
• The event was held at Kazan in Russia.
• Praveen Kumar was the first Indian man to win a gold medal at the Wushu World Championships.
• Praveen defeated Philippines' Russel Diaz in the 48kg category. 

Additional Information

• Wushu Sanda is a martial art which combines full-contact kickboxing, including close-range punches and kicks, with wrestling, takedowns, throws, sweeps and kicks catches.

Image is hidden in option 3 as followed.

Important functions of a database administrator are:

• Schema definition schema and physical organization modification granting of authorization for data access
• Monitoring jobs running on the database and ensuring that performance is not degraded by very expensive tasks submitted by some users.
• Routine maintenance includes activities like periodic ensuring that backup and enough freedisk space is available for normal operations and upgrading disk space as required.

The correct answer is Ramgarh.

Key Points

• Ramgarh Gas Thermal Power Station (RGTPP)-
  • Ramgarh Gas Thermal Power Station is the first gas thermal power plant of Rajasthan.
  • The first unit was commissioned on dated 15 November 1994 AD.
  • Location - Ramgarh, Jaisalmer
  • The present capacity of the plant is 270.50 MW.

Additional Information

• Dholpur Combined Cycle Power Plant is also a Gas Thermal Plant of Rajasthan with a capacity of 330 MW.
• Giral Thermal Power Plant is a lignite coal-based power project in Giral, Barmer.
• Chhabra Thermal Power Plant has 6 operational units with a capacity of 2320 MW.