Lenses (physics Only) (GCSE Physics)

What is the refractive index of a material in which light travels at 2.0 × 10^8 m/s? (Speed of light in vacuum ˜ 3.0 × 10^8 m/s.)

A camera lens produces a small aperture (large f-number). How does this affect depth of field and image brightness?

A student measures the focal length of a converging lens by focusing parallel sunlight to a point on a screen and measuring the distance from lens to screen. Which property makes this method accurate?

A monochromatic light beam strikes a glass–air boundary from inside the glass. The critical angle for the glass–air interface is 42°. If the angle of incidence inside the glass is 50°, what happens?

Light slows when entering glass from air. Which of the following explains why the wavelength changes but frequency remains the same?

An object 2.0 cm tall is placed 15 cm in front of a converging lens that produces an image 30 cm on the other side. What is the image height?

A thin lens produces a real image at 40 cm from the lens on the image side for an object placed 20 cm on the object side. What is the focal length?

The lens equation is 1/f = 1/u + 1/v (with sign convention). If an object is at infinity (u ? 8) for a lens, where does the image form?

Which ray rule is correct when drawing ray diagrams for a thin converging lens?

A thin converging lens forms an upright virtual image 12 cm tall when the object is 8 cm tall. What is the magnification and what does its sign indicate?

An object is placed 5 cm in front of a lens whose focal length is 10 cm. The image distance computed by thin lens equation is negative. Which best describes the image?