General Science and Technology Quiz

Zener diodes can operate via two breakdown mechanisms: Zener breakdown (dominates below 5V) and avalanche multiplication (dominates above 5V). In the transition region (3-5V), both mechanisms occur simultaneously, not exclusively.

To solve this question, the user needs to know the definition of thermal voltage and its value at room temperature.

Thermal voltage (VT) is the voltage equivalent of the thermal energy of a particle. It is given by the formula:

VT = kT/q

where k is the Boltzmann constant, T is the temperature in Kelvin, and q is the charge of a particle.

At room temperature (300K), the value of VT can be calculated as:

VT = (kT/q) = (1.38 x 10^-23 J/K x 300K) / 1.6 x 10^-19 C

Simplifying this expression, we get:

VT = 0.0259 V = 25.9 mV

Therefore, the answer is:

The Answer is: C. 26 mV

Fruits primarily contain sucrose, which is a disaccharide composed of glucose and fructose. While fruits also contain free glucose and fructose in varying proportions depending on the fruit type, sucrose is the dominant sugar form in most fruits, unlike lactose found only in milk or maltose in germinating grains.

An adult human skeleton has 206 bones, which includes 206 individual bones at birth. This number gradually decreases as bones fuse during growth and development, particularly in the skull, spine, and pelvis, resulting in the final adult count of 206 bones.

Glucose is a simple sugar that provides the quickest source of energy to the body as it doesn't need to be broken down further. It enters the bloodstream rapidly and is readily absorbed by cells. While carbohydrates and fats provide energy, they require more complex metabolic processes. Lipids are another term for fats.

Lactose is the natural sugar present in milk, making up about 4-5% of milk's composition. It is a disaccharide composed of glucose and galactose. Fructose is fruit sugar, maltose is found in germinating grains, and glucose is a simple sugar present in many foods but not specifically characteristic of milk.

The white color of milk is due to the presence of calcium and the reflection of light by casein proteins and fat globules. Calcium compounds contribute to the opaque white appearance. Iron is not responsible for milk's color, and while proteins and fats are present, calcium is the primary mineral responsible for the white coloration.

Tomato acts as a natural skin bleach due to its high vitamin C content and natural acidic properties. Vitamin C helps reduce melanin production and brighten skin tone. While all fruits listed have nutritional benefits, tomato specifically contains lycopene and vitamin C that promote skin lightening.

Hair is primarily made up of a protein called keratin, which is a fibrous structural protein. Keratin provides strength, rigidity, and protection to hair strands. The hair shaft is composed almost entirely of dead keratinized cells. Fats and lipids are not structural components of hair, and fructose is a sugar.

Hair is primarily composed of keratin, a fibrous structural protein that provides strength and protection to hair cells. The other options are not proteins found in hair - calcium and iron are minerals, while serotonin is a neurotransmitter.

A PIN diode has advantages over a normal p-n junction diode in both speed and current handling. The intrinsic region allows it to switch faster than regular diodes and handle higher current ratings due to its structure. This makes PIN diodes suitable for high-frequency applications like RF switches and attenuators.

A tunnel or Esaki diode is much more heavily doped than a normal p-n junction diode - typically about 1000 times higher doping concentration. This heavy doping creates a very narrow depletion region that allows electrons to tunnel through, creating the negative resistance characteristic that makes tunnel diodes useful in high-frequency oscillator circuits.

LEDs are typically constructed from gallium-based compound semiconductors like GaAs, GaP, or GaN, not from elemental semiconductors like Germanium (Ge) or Silicon (Si). These III-V compound materials have direct bandgaps that allow efficient light emission through electroluminescence, which Ge and Si cannot provide effectively.

Cryptology is the study of secret writing, including both cryptography (making secret codes) and cryptanalysis (breaking them). The term encompasses the entire field of secure communication techniques.

Exobiology (or astrobiology) is the study of life in outer space, including the search for extraterrestrial life and the study of how life might exist in extreme environments beyond Earth.

At higher altitudes (hills), atmospheric pressure is lower than at sea level. Lower pressure reduces the boiling point of water - typically about 1°C drop for every 285 meters of elevation. This is why water boils below 100°C on mountains.

The ozone hole was discovered in 1985 by British scientists from the British Antarctic Survey who were monitoring ozone levels over Antarctica. The Antarctic region experiences unique atmospheric conditions due to the polar vortex and extremely cold temperatures, which lead to ozone depletion during spring months.

Clickjacking is a malicious technique where attackers trick users into clicking on something different from what they perceive by overlaying invisible or disguised elements on a webpage. While option A mentions revealing confidential information, clickjacking is more broadly about deceiving users into performing unintended actions like deleting content, changing settings, or making unwanted purchases. The description in A captures the deceptive essence but is slightly narrow in focus.

Artificial satellites primarily use solar cells (photovoltaic cells) that convert sunlight directly into electrical energy. This is the most practical and reliable power source for satellites as they operate in space where sunlight is continuously available. Nuclear reactors are used only in specific large-scale missions, dynamos require mechanical rotation, and thermopiles produce insufficient power for satellite operations.