science & technology Online Quiz - 93

Ladislao Biro and his brother Georg Biro invented the modern ballpoint pen in the 1930s. Joseph Niepce worked with early photography, and Theodore Maiman developed the laser.

The barcode was patented by Norman Joseph Woodland and Bernard Silver in 1952. Their invention was inspired by Morse code patterns and initially used a bull's-eye design. Richard Trevithick is associated with steam locomotives, while Bartolommeo Cristofori invented the piano.

Evangelista Torricelli invented the mercury barometer in 1643, demonstrating that air has weight and creates pressure. His experiment using a mercury-filled glass tube fundamentally changed the understanding of atmospheric pressure. The unit of pressure 'torr' is named in his honor.

Alessandro Volta invented the first true battery, the voltaic pile, around 1800. His invention consisted of alternating zinc and copper discs separated by brine-soaked cardboard, producing steady electrical current. The electrical unit 'volt' is named in recognition of his pioneering work.

Jacques Cousteau and Emile Gagnan co-invented the aqualung in 1943, a self-contained underwater breathing apparatus that revolutionized diving. This device allowed divers to move freely underwater for extended periods. The Montgolfier brothers are famous for inventing the hot air balloon, not diving equipment.

Don Wetzel led the team that developed the first ATM in 1969 while working at Docutel. The invention transformed banking by enabling 24/7 cash access without visiting a bank branch. The first ATM was installed at a Chemical Bank in New York in 1969.

Kirkpatrick McMillan, a Scottish blacksmith, invented the first rear-wheel-driven bicycle around 1839. His design used treadles connected to driving rods to power the rear wheel. Earlier versions like the 'running machine' lacked any mechanism for self-propulsion.

Pierre and Ernest Michaux developed the first bicycle with pedal-crank drive in the 1860s. Their velocipede design attached pedals directly to the front wheel, creating a more efficient riding experience. John Dunlop invented pneumatic tires, not the crank mechanism.

An ideal gas perfectly follows Charles's law (V ∝ T at constant pressure) and Boyle's law (PV = constant at constant temperature). These two laws, along with Gay-Lussac's law, are fundamental gas laws that describe the behavior of ideal gases. Option B correctly identifies Charles's law and Boyle's law as essential for ideal gas behavior.

The ideal gas law is PV = nRT, where P is pressure, V is volume, n is moles of gas, R is the gas constant, and T is temperature. This equation combines Boyle's law, Charles's law, and Avogadro's law into one unified relationship. Option B shows the correct ideal gas law equation.

Molar heat capacity is defined as the heat required to raise the temperature of 1 mole of a substance by 1 K (or 1°C), not 10 K. The statement incorrectly uses 10 K instead of 1 K, making it false.

Dispersion forces (London forces) are weak attractive forces between molecules caused by temporary dipoles, not repulsive forces. Additionally, ideal gases by definition have no intermolecular forces at all. The statement is wrong on both counts.

Photons are particles of light that have zero rest mass. They are not 'very heavy' - they are massless particles. The statement is fundamentally incorrect.

Hund's rule deals with electron configuration in atoms - it states that electrons will occupy degenerate orbitals singly before pairing up. It has nothing to do with gas pressures, which are covered by Dalton's law of partial pressures.

The law of constant composition (Proust's law) states that a compound always contains the same elements in the same fixed ratio by mass. The law of multiple proportions (Dalton's law) is a different law dealing with ratios of elements in different compounds. They are not the same.