science & technology Online Quiz - 9

A transformer changes AC voltage levels using electromagnetic induction between coils. It steps voltage up (increases) or down (decreases) while maintaining power (minus losses). Transformers cannot convert DC to AC (that requires an inverter) or store electrical energy.

An anemometer is specifically designed to measure wind speed and direction. Hygrometers measure humidity, spectrometers analyze light spectra, and speedometers measure vehicle speed. The name comes from Greek 'anemos' (wind).

Geumaphobia is the fear of taste. The prefix 'geuma-' relates to taste. Gynophobia is fear of women, gnosiophobia is fear of knowledge, and arachnophobia relates to spiders (knees would be genuphobia).

Neophobia is the fear of newness, novelty, or new things. Thanatophobia is fear of death, nephophobia is fear of clouds, and achluophobia is fear of darkness. The prefix 'neo-' means new.

Chromatophobia is the fear of colors. The prefix 'chromato-' relates to color. Sitophobia is fear of food, chronophobia is fear of time, and cremnophobia is fear of precipices.

Phasmophobia is the fear of ghosts. Peniaphobia is fear of poverty, pedophobia is fear of children, and ergophobia is fear of work. The prefix relates to phantom or apparition.

Iatrophobia is the fear of doctors or going to the doctor. The prefix 'iatro-' relates to physicians or healing. Toxicophobia is fear of poison, ichthyophobia is fear of fish, and ideophobia is fear of ideas.

Saturn is the only planet in our solar system with an average density less than water (0.69 g/cm³ vs water's 1 g/cm³). This means if you could find a body of water large enough, Saturn would float on it. The planet is composed mostly of hydrogen and helium gases, making it extremely light relative to its size. Jupiter also has low density but still greater than water.

The Moon is drifting away from Earth at approximately 3.8 centimeters per year. This gradual increase in distance is caused by tidal interactions - Earth's rotation transfers angular momentum to the Moon's orbit through tidal bulges. Over billions of years, this has caused the Moon to slowly recede. The rate has varied throughout Earth's history but averages around 3.8 cm/year currently.

Two pieces of metal can become permanently stuck together in space through a phenomenon called cold welding. In the vacuum of space, there's no air or oxide layer between clean metal surfaces, allowing direct metallic bonding when they touch. On Earth, oxidation and contaminants prevent this. The effect requires very clean, smooth surfaces and was first observed with spacecraft components.

About 55% of Americans correctly identify the sun as a star according to science literacy surveys. This statistic reflects a significant gap in basic astronomical knowledge among the adult population. Options A (65%) and C (45%) are close but not the documented finding from National Science Foundation surveys.

1 Joule equals 10^7 ergs because the erg is the CGS (centimeter-gram-second) unit of energy, while the Joule is the SI (meter-kilogram-second) unit. The conversion follows from 1 Joule = 1 Newton-meter = 1 kg·m²/s², and 1 erg = 1 dyne-centimeter = 1 g·cm²/s². Since 1 kg = 1000 g and 1 m = 100 cm, the conversion factor is 10^7.

The adult human body typically contains 206 bones. This includes the axial skeleton (skull, spine, ribs, sternum) and the appendicular skeleton (limbs and girdles). Babies are born with around 270 bones, which fuse together as they grow.

Carbon-14 (radiocarbon) forms when cosmic ray neutrons collide with nitrogen-14 atoms in the upper atmosphere, transmuting them into radioactive carbon-14. This continuous production maintains the steady-state concentration of radiocarbon used in radiometric dating.

Blotting paper contains numerous tiny pores that create capillary tubes. Ink is drawn into these pores by capillary action - the combined effect of adhesive forces between ink and paper fibers and cohesive forces within the liquid itself.

A siphon operates due to the pressure difference created by a height difference between liquid levels. When both vessels have liquid at the same level, there's no gravitational pressure gradient to drive flow, causing the siphon to fail regardless of tube configuration.