Physics: Optics and Waves Flashcards

A diverging lens always produces images that are:

Answer: Virtual, upright, and reduced

A diverging (concave) lens always produces virtual, upright, and reduced images regardless of object position.

The phenomenon of diffraction is most pronounced when the wavelength of light is:

Answer: Comparable to or larger than the aperture

Diffraction effects are significant when the wavelength is comparable to or larger than the size of the aperture or obstacle.

Two sources emit coherent light with wavelength 500 nm. For constructive interference, the path length difference must be:

Answer: Any integer multiple of λ

Constructive interference requires the path difference Δ = mλ where m = 0, ±1, ±2, … (integer multiples of the wavelength).

Which property of light is demonstrated when polarized light passes through a second polarizer oriented at 90°?

Answer: Polarization (extinction)

When two polarizers are crossed (90° to each other), no light passes through, demonstrating the transverse polarization of light.

A myopic (nearsighted) eye is corrected with a:

Answer: Diverging (concave) lens

Myopia is caused by the eye focusing images in front of the retina; a diverging lens diverges rays before they enter the eye, correcting this.

The speed of light in a vacuum is approximately:

Answer: 3 × 10⁸ m/s

The speed of light in vacuum is c ≈ 3 × 10⁸ m/s (exactly 299,792,458 m/s).

A wave has frequency 440 Hz and wavelength 0.75 m. Its speed is:

Answer: 330 m/s

Wave speed v = fλ = 440 Hz × 0.75 m = 330 m/s (the speed of sound in air at room temperature).