This set of Engineering Physics Multiple Choice Questions & Answers (MCQs) focuses on “Nanoscience and Nanotechnology”.
1. Nanomaterials are the materials with at least one dimension measuring less than ___________
a) 1 nm
b) 10 nm
c) 100 nm
d) 1000 nm
Explanation: A material with at least one of its dimensions measuring less than 100 nm (1 to 100nm) are classified as nanomaterials.
2. A material with one dimension in Nano range and the other two dimensions are large is called ___________
b) Quantum wire
c) Quantum well
d) Quantum dot
Explanation: Such a material with one dimension in Nano range and other two large is called quantum well. A material with two of the three dimensions in the nano range and third large is called quantum wire. When all the dimensions are in nano range, it is called quantum dot.
3. The colour of the nano gold particles is ___________
Explanation: The colour of the nano gold particle varies with the size of the particles. It shows different colours like orange, red, purple, or greenish.
4. The melting point of particles in nano form ___________
c) Remains same
d) Increases then decreases
Explanation: For the particles in the nano form, the melting point reduces significantly. Other chemical properties are also changed as the dimensions of the object comes in the nano range.
5. The first talk about nano-technology was given by ___________
a) Albert Einstein
c) Gordon E. Moore
d) Richard Feynman
Explanation: In 1959, Richer Feynman gave a speech in which he spoke of nano-science and nano-technology. He talked about the possibility of manipulating individual atoms and molecules.
6. Which of the processes of materials was not described as Nanotechnology?
Explanation: Nanotechnology, as defined by Professor N. Taniguchi, consists of the processing, separation, consolidation and deformation of materials by one atom or by one molecule. It is used exclusively for the nanomaterials.
7. The initial tools used to help launch the nanoscience revolution were ___________
c) Scanning probe instruments
Explanation: Scanning probe instruments were the initial tools used by the scientist. In these instruments, the probe slides along the surface of the specimen.
8. When semiconductors are reduced to nanometres they become pure conductors.
Explanation: When semiconductors are reduced to the nano form their chemical properties change significantly and they become insulators, as there is no more space for free electrons to move.
9. The major difference between the nano materials compared to the bulk form is the big fraction of the total number of atoms on the surface.
Explanation: As the bulk material is changed into nano form, the number of atoms on the surface turns out to be a large fraction of the total number of atoms present in the material. Due to this, the whole physical/chemical properties of the material changes.
10. The size of atoms is nearly ____________
a) 0.01 nm
b) 0.1 nm
c) 1 nm
d) 10 nm
Explanation: The size of the atoms is nearly 0.1 nm. The smallest naturally occurring atom, helium, is 0.1 nm in size. Thus, nanotechnology can be used to study their characteristics and properties or even control them.
Sanfoundry Global Education & Learning Series – Engineering Physics.
To practice all areas of Engineering Physics, here is complete set of 1000+ Multiple Choice Questions and Answers.