Science & Technology General Knowledge Quiz

Dog whistles produce ultrasonic sounds (above 20 kHz) which are beyond the range of human hearing but within dogs' hearing range. Dogs can hear frequencies up to about 45-65 kHz, much higher than humans. Infrasound (below 20 Hz) would not be useful for dog training as dogs also have limited sensitivity there.

Ultrasonic sound is defined as sound waves with frequencies above 20 kHz (20,000 Hz), which is the upper limit of human hearing. The human audible range is 20 Hz to 20 kHz, so anything above 20 kHz is ultrasonic. Ultrasound is used in medical imaging, cleaning, and various industrial applications.

SONAR (Sound Navigation and Ranging) works on the principle of echo - sound waves are emitted, reflected back from objects, and the time delay gives distance/depth. Superposition principle refers to wave interference, which is not the core concept here.

LHC stands for Large Hadron Collider, the world's largest particle accelerator located at CERN. It collides protons at near-light speed to study fundamental particles. 'Hadron' refers to composite particles like protons and neutrons.

Intel was founded as Integrated Electronics, from which the name Intel was derived. The company was founded in 1968 and became the world's largest semiconductor chip maker. The name reflects their focus on electronic components.

PNG stands for Portable Network Graphics, a lossless image compression format. It was developed as an improved replacement for GIF. The name reflects its portability across different platforms and network-friendly design for web use.

MIME stands for Multipurpose Internet Mail Extensions, an internet standard that extends email format to support text, images, audio, video, and other non-text attachments. It allows email systems to handle diverse content types beyond plain text.

Radon is the odd one out because it's a noble gas (Group 18), while chlorine, fluorine, astatine, and iodine are all halogens (Group 17). Halogens are highly reactive nonmetals, while noble gases are largely inert. Radon is also radioactive and gaseous at room temperature.

Kilowatt (kW) is the odd one out because it's a unit of POWER (rate of energy use), while joule, calorie, and kilowatt-hour are all units of ENERGY or work done. Power = Energy / Time, so 1 kW = 1 kJ/s. The kilowatt-hour (kWh) is a unit of energy equal to 1 kW used for 1 hour.

'Breakbone fever' is a traditional name for dengue fever, referring to the severe joint and muscle pain it causes. Dengue is a mosquito-borne viral disease prevalent in tropical and subtropical regions, transmitted by Aedes mosquitoes, unlike malaria (caused by Plasmodium parasites), typhoid (bacterial infection), or tuberculosis (bacterial lung infection).

The Milky Way galaxy has a spiral shape, specifically a barred spiral galaxy. It consists of a central bar-shaped structure with spiral arms extending outward. The disc shape (option A) is partially correct but incomplete - it's specifically a spiral disc, not a flat disc. Circular and irregular are incorrect classifications for the Milky Way.

Drake's Equation is N = N* × fp × ne × fl × fi × fc × fL, used to estimate the number of active, communicative extraterrestrial civilizations in the Milky Way galaxy. It was formulated by astrophysicist Frank Drake in 1961. Option B is Fermat's Last Theorem (proven by Andrew Wiles). Option C is related to the Golden Ratio. Option D is not a standard equation.

A light year is a unit of distance, specifically the distance that light travels in one vacuum year (approximately 9.46 trillion kilometers or 5.88 trillion miles). It is commonly used to measure astronomical distances. Students often confuse it with a unit of time because of the word 'year' in the term, but it measures distance, not time.