Physics

The Boltzmann constant (K) is related to the universal gas constant (R) and Avogadro's number (Na) by the formula K = R / Na. This expresses the gas constant per individual molecule rather than per mole.

A rainbow is formed when sunlight is refracted, reflected, and dispersed by raindrops. To see a rainbow, the observer must have the Sun behind them and be facing the raindrops where the light is refracted. Therefore, the Sun remains behind us and we face the raindrops.

Young's modulus measures the stiffness of a material and is defined only for solids, as it relates to elastic deformation under tensile or compressive stress. Gases and liquids do not have a defined Young's modulus because they cannot sustain shear stress in the same way solids do.

Matter inherently possesses energy due to its mass, known as rest energy, which is described by Einstein's equation E=mc². This energy exists even when the matter is at rest, distinguishing it from other forms like potential or chemical energy.

Each electron carries a charge of approximately -1.6 × 10⁻¹⁹ coulombs. For one million (10⁶) electrons, the total charge is 10⁶ × (-1.6 × 10⁻¹⁹) = -1.6 × 10⁻¹³ coulombs. Therefore, the correct answer is option B: -1.6 × 10⁻¹³ coulombs.

Transistors operate based on electrical current and voltage applied to their terminals, not by heating any part. Therefore, none of the options involving heating the emitter, base, or collector are correct.

Light Emitting Diodes (LEDs) are semiconductor diodes specifically designed to emit light when current passes through them, making them ideal as indicator lamps in electronic circuits.

Internal energy is a state function representing the total energy contained within a system, including kinetic and potential energies at the molecular level. However, it is not simply the sum of all forms of energy associated with molecules, nor is it proportional only to translational kinetic energy. Therefore, option B is correct.

Semiconductors doped with donor atoms have extra free electrons, making them n-type semiconductors. P-type semiconductors have acceptor atoms creating holes, and 'mix' or 'any of above' are not standard classifications.

A non-inverting amplifier configuration typically has a very high input impedance because the input signal is applied to the non-inverting input of the op-amp, which draws negligible current. This characteristic is fundamental to its operation.