Physics

Optically active crystals rotate the plane of polarization of polarized light passing through them. This phenomenon is known as optical rotation or optical activity, and it specifically affects the polarization plane.

Newton's 2nd law of motion states that force is equal to mass times acceleration (F = ma), thus it defines the relationship between both force and acceleration, not just acceleration alone.

When white light is used in Young's double slit experiment, the different wavelengths interfere to produce colored fringes due to the superposition of various colors, resulting in a spectrum of colors in the interference pattern.

A point source of light in a homogeneous medium emits light equally in all directions, producing a spherical wave front as the wave propagates outward uniformly.

Sound waves are longitudinal mechanical waves and cannot be polarized because their oscillations occur in the direction of propagation. In contrast, radio waves, ultraviolet rays, and X-rays are electromagnetic waves and can be polarized.

The resistance of a metallic wire increases with temperature because the atoms vibrate more at higher temperatures, causing more collisions for the electrons and thus increasing resistance.

When two bodies move toward each other, their relative speed is the sum of their speeds, which equals 6 m/s. When they move in the same direction, the relative speed is the difference of their speeds, which equals 4 m/s. Solving these equations: x + y = 6 and x - y = 4 gives speeds 5 m/s and 1 m/s.

For bulbs rated at the same voltage, higher wattage means higher power consumption and thus lower resistance, since Power = Voltage² / Resistance. Therefore, the 200 watt bulb has less resistance than the 100 watt, 300 watt, or 60 watt bulbs at the same voltage.

The human ear is most sensitive to sounds in the frequency range of approximately 2000 to 4000 hertz, which corresponds to the frequencies where speech sounds are concentrated and where hearing sensitivity peaks.

In plane polarized light, the vibrations of the electric field occur in a single plane perpendicular to the direction of propagation. This means the vibration direction is perpendicular to the light's travel direction, making option C correct.