Physics

When a second electron is brought closer to the first electron, both being negatively charged, the electrostatic potential energy increases due to the repulsive force between like charges. This increase reflects the work done against the repulsion to bring them closer.

Two parallel beams of positrons, which are positively charged particles, will repel each other due to the electrostatic repulsion between like charges. This is consistent with Coulomb's law, where like charges repel.

When a stone is thrown from the top of a tall building, it follows a projectile motion under gravity, which traces a parabolic path. This is because the horizontal velocity is constant while the vertical velocity changes uniformly due to gravity, resulting in a parabolic trajectory.

Approximately one-sixth of an iceberg's volume is visible above the water surface because ice is less dense than seawater, causing most of it to be submerged. This is a well-known fact in physics related to buoyancy and density.

Copper is a metal, and its resistance decreases as temperature decreases because electron scattering reduces. Germanium is a semiconductor, and its resistance increases as temperature decreases because fewer charge carriers are thermally excited at lower temperatures.

An adiabatic process is one in which no heat is exchanged with the surroundings, and it is often called an isentropic process because it occurs at constant entropy in an ideal reversible case.

In thermodynamics, a state function is a property whose value depends only on the current state of the system, not on the path taken to reach that state. Internal energy is a classic example of a state function. Pressure and volume are also state functions because they describe the state of the system at equilibrium. Heat supply, however, is a path function because it depends on the process or path taken during a change of state. Although pressure and volume are state functions, internal energy is the best example commonly emphasized as a state function in thermodynamics, especially in the context of energy changes.

The first overtone of a stretched string corresponds to the second harmonic, which has twice the frequency of the first harmonic. Given the first overtone frequency is 320 Hz, the first harmonic frequency is half of that, i.e., 160 Hz.

A heat engine must operate in a cyclic process and between two reservoirs at different temperatures to convert heat into work successfully. Both conditions are essential for its operation.

The average acceleration due to gravity near the Earth's surface is approximately 32 feet per second squared (ft/s²). This means the velocity of a falling object increases by about 32 feet per second every second.