Tag: logic gates

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Questions Related to logic gates

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

State whether true or false :
Tensile strength of nano-material is greater than that of steel.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Because of its very small size, the nano-material has tensile strength greater than that of steel. 

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

State whether True or False :
At nanoscale, laws of Newtonian mechanics fail.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Quantum mechanics is required to understand the behavior of nanoscale systems because Newtonian theories collapse and fail at this scale. If Newtonian laws governed the working of atoms, then negatively charged electrons would be attracted to the positively charged nucleus of the atoms and the two would collide, but this does not happen.

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

State whether true or false :
Nano-materials with same dimensions but with different structure might have different physical properties.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nano-materials have the dimensions of about 1-100 nanometers, their material properties change significantly. This is the size scale where quantum effects rule the behavior and properties of particles. Properties of materials depend on size and structure of the material. Even if size is same but the structure of the material is different,  physical properties like melting point, electrical conductivity, etc changes.

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

For nano-structured materials, the surface area to volume ratio is : 

  1. large

  2. small

  3. very small

  4. can't say
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nano-particles have a relatively larger surface area when compared to the same volume of the material.
For example: Consider a sphere of radius r. 

Surface area of sphere $=4\pi r^{2}$
Volume of sphere $=\dfrac{4}{3}\pi r^{3}$ 

It means given volume is divided into smaller piece, the surface area increases. So, we conclude that surface area to volume ratio is very large for nano-particles. Since nano-particles have a very small size, r is small, so the ratio of surface area to volume is very large.

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

State whether true or false :
Carbon nanobuds has mixed properties of both fullerenes and nanotubes. 

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Carbon nanobud is a material that combines carbon nanotubes and spheroid fullerenes, both allotropes of carbon, in the same structure, forming "buds" attached to tubes. Consequently, nanobuds exhibit the properties of both carbon nanotubes and fullerenes.

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

State whether true or false :
The greater the surface area for the same volume, the lesser would be the reactivity. 

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Greater the surface area, greater are the reaction rates.
This is because reaction occurs when particles in gas/liquid collide with the particles in solid. Increasing the surface area of solid increases the chances of collision taking place. So, reaction rate increases as the surface area is increased.

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

Which of the following methods can be used to obtain nano sized materials ?

  1. Ball-mills methods

  2. Inert-gas condensation technique

  3. Wet-chemical technique

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Different physical, chemical, biological methods such as ball milling, inert gas condensation, wet chemical methods are used for obtaining nano-sized materials. So answer is (d) All of the above. 

Multiple choice nanoscience and nanotechnology nanotechnology logic gates

Which of the following element is a major constituent in the conventional sources of energy ?

  1. Hydrogen

  2. Oxygen

  3. Carbon

  4. Aluminium
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Conventional sources of energy include coal, petroleum, natural gas, wood etc. Carbon is their main constituent.