Tag: the concept of bernoulli's principle

Questions Related to the concept of bernoulli's principle

Which of the following is a property of air?

  1. Air has mass

  2. Air occupies space

  3. Air expands when heated

  4. All of the above


Correct Option: D
Explanation:

Air has mass, air occupies space and air expands when heated are all properties of air.

The experiment conducted using glass filled with water and card board indicates that _________. 

  1. Air has mass

  2. Air occupies space

  3. Air expands when heated

  4. Air exerts pressure


Correct Option: D
Explanation:

The experiment conducted using glass filled with water and card board indicates that air exerts pressure.

Which of the following is an air pollutant?

  1. $N _2$

  2. $CO _2$

  3. $O _2$

  4. $CO$


Correct Option: D
Explanation:

Carbon monoxide is an air pollutant whereas carbon dioxide is considered as a greenhouse gas.

Which of the following doesn't show that air exerts pressure?

  1. Riding a bicycle against wind

  2. Flying a kite

  3. Ball falling to the ground

  4. Drinking a soft drink through a straw


Correct Option: C
Explanation:

A ball falling down to the ground is due to gravity and not due to air pressure. Hence, it doesn't show that air exerts pressure.

What is the best thing to do when strong winds are blowing over a hut having a weak thatched roof?

  1. Open the doors and windows

  2. Close all the doors and windowns

  3. Make holes in the roof

  4. Burn wood inside


Correct Option: A
Explanation:

When winds blow over a week roof, it creates a low pressure over it and a high pressure inside causing the roof to be blown off. Opening the doors and windows reduces this pressure difference and avoids the roof from being blown off.

So, the correct answer is open the doors and windows

During the takeoff of an aeroplane there is a _____________pressure on the top and a _____ pressure below.

  1. Low, low

  2. Low, high

  3. High, high

  4. High, low


Correct Option: B
Explanation:

Because of the curved upper surface of the aeroplane more air flows in the same time as compared to the lower surface. Therefore, the pressure over the aeroplane is less when compared to the lower surface.

So, the answer is low , High

Overhead cables need not be insulated because :

  1. air is a bad conductor of electricity

  2. air is a good conductor of electricity

  3. bare wires conduct electricity better than insulated wires

  4. none of these


Correct Option: A
Explanation:

As we know air is a bad conductor (It consists of mostly nitrogen and oxygen which are electrically neutral and are not easily ionized) of electricity. So, Overhead cables need not be insulated.

State True or False.

During day time, due to sea breeze, the sailing boats sail towards the land.

  1. True

  2. False


Correct Option: A
Explanation:

Sea breeze is a breeze blowing towards the land from the sea, especially during the day owing to the relative warmth of the land

Water drops freeze and fall as:

  1. Ice

  2. Hail

  3. Both

  4. None of these


Correct Option: A
Explanation:

On freezing water drops they converted in ice.


If there's enough room between the warmer air and the ground, the water droplets refreeze in a bottom layer of below freezing air and fall as sleet.

The humidity of a place:

  1. lies between 10% -20%

  2. is always more than 50%

  3. is always less than 80%

  4. varies from time to time


Correct Option: D
Explanation:

The humidity of a place varies from time to time as it also depends on the place we reside in. Coastal areas have more humidity or is more humid due to the pressure of the sea breeze.