4.For Tutor Adil B Only! For Tutor Adil B Only! For Tutor Adil B Only! For Tutor Adil B Only! For Tutor Adil B Only!
7.Photon has mass or not? I am confused, since we say, it has zero rest mass but how does it is affected by gravity then?
Nanotechnology is an advanced field of study of materials and things on subatomic levels - atoms and molecules. It is the design, production and development of structures of size and shape at nanometer scale. Nanotechnology manipulates the dimension of matter sized from 1 to 100 nanometers. The application of nanotechnology is diverse in the field of semiconductors, energy science, molecular biology and energy storage.
Question 1: The melting point of nanoparticles ___________.
a) increases b) decreases
c) both (a) and (b) d) none of these
Explanation: In nanoparticles, as the dimensions come in the nano range, the melting point reduces significantly. Therefore, the melting point of nanoparticles decreases.
Question 2: A one atom sheet of carbon is known as __________.
a) graphene b) graphite
c) diamond d) none of these
Explanation: Graphene is one atom thick layer of carbon that is extremely strong and conducts electricity.
Question 3: __________ is the most important property of nanomaterial.
a) Pressure b) Temperature
c) Hardness d) Friction
Explanation: Nanotechnology helps in reducing friction considerably and improves the durability of material.
Question 4: The size of atom of nanomaterial is nearly _________
a) 0.01 nm b) 0.1 nm
c) 10 nm d) 1 nm
Answer: 0.1 nm
Explanation: The size of atoms of nanomaterials ranges in the order of 0.1 nm. The smallest naturally occurring atom, helium, is 0.1 nm in size.
Question 5: _____________ are the class of structures made of rolled up carbon lattices.
a) Fullerenes b) Nanobars
c) Graphite d) Nanotubes
Explanation: Nanotubes are hollow tubular nanostructures, which consist of multiple carbon layers wrapped to form a hollow core.
Question 6: Nanotechnology was introduced into modern physics by _____________
a) Albert Einstein b) Max Planck
c) Richard Feymann d) Issac Newton
Answer: Richard Feymann
Explanation: Physicist Richard Feymann introduced the concept of nanotechnology in 1959.
Question 7: The ratio of ___________ and __________ describes the efficiency of nano substances.
a) surface area, volume. b) pressure, volume
c) weight, volume d) volume, weight
Answer: surface area, volume.
Explanation: The large surface area to volume ratio in nanomaterials enhances the performance of nanomaterials. These are highly desirable in the chemical reactions inside batteries and catalysts.
Question 8: Which of the following fields complement the study of nanoscience and nanotechnology?
a) Newtonian mechanics b) Classical mechanics
c) Quantum mechanics d) All of these
Answer: Quantum mechanics
Explanation: Nanotechnology utilises quantum mechanics to study different effects in nanoparticles at a very small scale. Quantum nanoscience is the intersecting space of science at quantum and nano levels.
Question 9: Which of the following processes of material is described as nanotechnology?
a) Consolidation b) Separation
c) Processing d) All of these
Answer: All of these
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.
Question 10: When semiconductors are reduced to the nano form, they become ____________.
a) pure semiconductor b) conductor
c) insulator d) none of these
Explanation: When semiconductors are reduced to the nano form, their chemical properties change and there are no spaces available for free electrons to move. Therefore, it becomes an insulator.