List of top Questions asked in CBSE CLASS XII

You are Aruna/Arun, Head girl/Head boy of Kohinoor Public School, Hawapuri. Your school is organising an inter-house book review competition. Draft a notice informing the students of classes IX–XII about the competition and invite registrations for the same. Include other necessary details. Put your notice in a box.
Draw the labelled layout of a cold storage plant.
Describe the importance of an overload protector with the help of a diagram.
What main points must be kept in view while designing the air distribution system of an air conditioning system?
Write the properties of R-12.
Explain the ‘Radial Perimeter’ duct system with the help of a diagram.
Explain the Unitary air conditioning system.
Give an example of an eco-friendly refrigerant and also write its properties.
Mention the qualities of a successful entrepreneur.
Write any four advantages of green jobs.
Describe the process of ‘Chemical dehumidification’.
Describe the preservation of meat products.
What is a refrigerant? Give two examples.
What do you understand by ‘Heat Transfer’? Write the different modes of heat transfer.
Differentiate between Blower and Exhauster.
Describe the psychrometric process used for ‘summer air conditioning’.
The relay which is connected in series with the running winding is:
The refrigerant R-22 is:
This insulating material operates best in the temperature range of \(-200^\circ C\) to \(150^\circ C\) :
In ‘Shell and Tube’ condenser:
Write any two barriers to active listening.
Give two examples of extrinsic motivation.
Write some components of a spreadsheet.
The passage carrying conditioned air to the conditioned space is known as:
In a window air conditioner, ............ type of evaporator is used.