Nanotechnology — Set 5
Technology · नैनो प्रौद्योगिकी · Questions 41–50 of 50
What is one nanometer equal to?
Correct Answer: B. 10^-9 meters
• **10^-9 meters** = A nanometer is a metric unit of length equal to one-billionth of a meter. • **Key significance** — It is represented as $10^{-9}$ meters in scientific notation. • 💡 Wrong-option analysis: A: 10^-6 meters is a different concept; C: 10^-12 meters is a different concept; D: 10^-3 meters is a different concept.
Which allotrope of carbon is the basic structural element of carbon nanotubes?
Correct Answer: B. Graphene
• **Graphene** = Graphene is a single layer of carbon atoms arranged in a hexagonal lattice. • **Key significance** — Carbon nanotubes are essentially sheets of graphene rolled into cylinders. • 💡 Wrong-option analysis: A: Diamond is a different concept; C: Coal is a different concept; D: Graphite is a different concept.
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
• **1959** = Richard Feynman gave this landmark lecture at Caltech in 1959. • **Key significance** — He discussed the possibility of manipulating individual atoms to create tiny machines. • 💡 Wrong-option analysis: A: 1945 is a different concept; C: 1974 is a different concept; D: 1981 is a different concept.
Which instrument is used to visualize objects at the nanoscale, as they are too small for visible light?
Correct Answer: A. Electron Microscope
• **Electron Microscope** = Electron microscopes use a beam of electrons instead of light to achieve much higher magnification. • **Key significance** — Nanoparticles are smaller than the wavelength of light, so they cannot be seen with ordinary microscopes. • 💡 Wrong-option analysis: B: Optical Microscope is a different concept; C: Stethoscope is a different concept; D: Telescope is a different concept.
Fullerenes, discovered in 1985, are shaped like which common object?
Correct Answer: B. Soccer ball
• **Soccer ball** = The most common fullerene, C60, is shaped like a hollow sphere resembling a soccer ball. • **Key significance** — They are named after Buckminster Fuller for their resemblance to his geodesic domes. • 💡 Wrong-option analysis: A: Donut is a different concept; C: Cube is a different concept; D: Pyramid is a different concept.
Which property of nanoparticles is most important for their use in catalysts?
Correct Answer: B. High surface area
• **High surface area** = Nanoparticles have a very high surface area compared to their volume. • **Key significance** — This allows more atoms to be exposed to reactants, significantly speeding up chemical reactions. • 💡 Wrong-option analysis: A: High density is a different concept; C: Low weight is a different concept; D: Transparency is a different concept.
Nanotechnology is often used to create 'self-cleaning' windows. This is based on which property?
Correct Answer: B. Superhydrophobicity
• **Superhydrophobicity** = The self-cleaning property of windows created using nanotechnology is based on Superhydrophobicity. • **Key significance** — 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. • 💡 Wrong-option analysis: A: Hydrophilicity is a different concept; C: Transparency is a different concept; D: Radioactivity is a different concept.
What is the meaning of the prefix 'nano' in the word nanotechnology?
Correct Answer: A. Dwarf
• **Dwarf** = The word 'nano' comes from the Greek word 'nanos', which means dwarf. • **Key significance** — It is used as a prefix to indicate a factor of one-billionth. • 💡 Wrong-option analysis: B: Huge is a different concept; C: Fast is a different concept; D: Invisible is a different concept.
Which sector uses 'Quantum Dots' for more vibrant and energy-efficient displays?
Correct Answer: B. Electronics
• **Electronics** = The correct answer is 'Electronics'. • **Key significance** — Quantum dots are nanometer-sized semiconductor particles that emit specific colors of light. • 💡 Wrong-option analysis: A: Agriculture is a different concept; C: Textile is a different concept; D: Construction is a different concept.
In medicine, 'Nanobots' are being researched for which primary purpose?
Correct Answer: B. Targeted drug delivery inside the body
• **Targeted drug delivery inside the body** = Nanobots or nanoparticles can be engineered to deliver drugs directly to cancer cells while leaving healthy cells alone. • **Key significance** — This reduces side effects and makes treatment more effective. • 💡 Wrong-option analysis: A: Replacing doctors is a different concept; C: Building hospitals is a different concept; D: Making medicine taste better is a different concept.