Nanotechnology — Set 5
Technology · नैनो प्रौद्योगिकी · Questions 41–50 of 50
What is one nanometer equal to?
Correct Answer: B. 10^-9 meters
A nanometer is a metric unit of length equal to one-billionth of a meter. It is represented as $10^{-9}$ meters in scientific notation. This scale is roughly the size of a few atoms.
Which allotrope of carbon is the basic structural element of carbon nanotubes?
Correct Answer: B. Graphene
Graphene is a single layer of carbon atoms arranged in a hexagonal lattice. Carbon nanotubes are essentially sheets of graphene rolled into cylinders. Graphene is also known for being one of the strongest materials ever tested.
Richard Feynman is associated with the early concepts of nanotechnology. In which year did he give his famous talk 'There’s Plenty of Room at the Bottom'?
Correct Answer: B. 1959
Richard Feynman gave this landmark lecture at Caltech in 1959. He discussed the possibility of manipulating individual atoms to create tiny machines. This talk is considered the birth of the conceptual framework for nanotechnology.
Which instrument is used to visualize objects at the nanoscale, as they are too small for visible light?
Correct Answer: A. Electron Microscope
Electron microscopes use a beam of electrons instead of light to achieve much higher magnification. Nanoparticles are smaller than the wavelength of light, so they cannot be seen with ordinary microscopes. Two common types are SEM (Scanning) and TEM (Transmission).
Fullerenes, discovered in 1985, are shaped like which common object?
Correct Answer: B. Soccer ball
The most common fullerene, C60, is shaped like a hollow sphere resembling a soccer ball. They are named after Buckminster Fuller for their resemblance to his geodesic domes. They have significant potential in medicine and electronics.
Which property of nanoparticles is most important for their use in catalysts?
Correct Answer: B. High surface area
Nanoparticles have a very high surface area compared to their volume. This allows more atoms to be exposed to reactants, significantly speeding up chemical reactions. This efficiency is a major reason for their use in industrial catalysis.
Nanotechnology is often used to create 'self-cleaning' windows. This is based on which property?
Correct Answer: B. Superhydrophobicity
The self-cleaning property of windows created using nanotechnology is based on Superhydrophobicity. Superhydrophobicity is a surface property where water contact angle exceeds 150°, causing water droplets to bead up and roll off, carrying dirt and dust away. This property, inspired by the 'Lotus Effect' of lotus leaves, is achieved by creating nano-scale surface textures that repel water completely.
What is the meaning of the prefix 'nano' in the word nanotechnology?
Correct Answer: A. Dwarf
The word 'nano' comes from the Greek word 'nanos', which means dwarf. It is used as a prefix to indicate a factor of one-billionth. In science, it refers to the study and manipulation of matter at extremely small dimensions.
Which sector uses 'Quantum Dots' for more vibrant and energy-efficient displays?
Correct Answer: B. Electronics
The correct answer is 'Electronics'. Quantum dots are nanometer-sized semiconductor particles that emit specific colors of light. They are used in the latest generation of televisions and monitors to improve color accuracy. They are also being researched for use in high-efficiency solar cells.
In medicine, 'Nanobots' are being researched for which primary purpose?
Correct Answer: B. Targeted drug delivery inside the body
Nanobots or nanoparticles can be engineered to deliver drugs directly to cancer cells while leaving healthy cells alone. This reduces side effects and makes treatment more effective. This area of study is part of a field called nanomedicine.