When light passes through two crossed polarizers (90 degrees apart), no light is transmitted, resulting in zero intensity.

Using Malus's law, the transmitted intensity I = I_0 * cos²(θ). For θ = 30 degrees, I = I_0 * (√3/2)² = (3/4)I_0.

When the angle of incidence exceeds the critical angle, the light ray undergoes total internal reflection and is reflected back into the denser medium.

At the critical angle, the light ray is refracted at 90°, traveling along the boundary between the two media.

The magnetic field inside a long solenoid is directly proportional to the current flowing through it. Increasing the current increases the magnetic field strength.

Reversing the current reverses the direction of the magnetic field.

The magnetic field inside a solenoid is directly proportional to the current flowing through it; thus, it increases with an increase in current.

The magnetic field inside a solenoid is directly proportional to the current flowing through it, so increasing the current increases the magnetic field.

When a magnet is cut in half, each half becomes a smaller magnet with its own north and south poles, resulting in two smaller magnets.

The magnetic field strength is directly proportional to the current, so it halves.

The magnetic field strength decreases with the square of the distance from the wire.

The magnetic field strength around a long straight conductor is inversely proportional to the distance from the conductor. Therefore, if the distance is doubled, the magnetic field strength halves.

The magnetic field strength inside a long solenoid is directly proportional to the current flowing through it; thus, it increases with an increase in current.

The magnetic field strength around a long straight conductor decreases inversely with distance, so it halves when the distance is doubled.

The moment of inertia can change when rotating about an axis that is not a principal axis due to the distribution of mass relative to the new axis.

Increasing the resistance of the wire decreases the current, which causes the null point to move away from the battery.

Increasing the intensity of light increases the number of photons incident on the surface, leading to more emitted electrons, provided the frequency is above the threshold.

Increasing the intensity of light increases the number of photons, which in turn increases the number of emitted electrons, provided the frequency is above the threshold.

Increasing the voltage increases the photoelectric current by attracting more emitted electrons.

If the incident light is below the threshold frequency, no electrons are emitted.

Cooling the metal surface reduces the thermal energy of the electrons, making it harder for them to overcome the work function.

As the frequency of a sound increases, its pitch also increases.

When light passes through a polarizer at an angle of 45 degrees, it becomes partially polarized.

When a capacitor is fully charged, the potential difference across its plates becomes maximum and remains constant until it is discharged.

Increasing the resistance of the wire decreases the current, which in turn decreases the potential difference across any segment of the wire.

If the length of the segment is halved, the potential difference across that segment also halves, assuming the potential gradient remains constant.

In a fluid at rest, pressure increases with depth due to the weight of the fluid above.

According to Gay-Lussac's Law, if the temperature increases at constant volume, the pressure increases.

According to Boyle's law, if the volume is halved at constant temperature, the pressure doubles.

According to Boyle's law, if the volume of a gas is halved while keeping the temperature constant, the pressure doubles.