Lenses (physics Only) (GCSE Physics)

A diverging (concave) lens always produces an image that is:

A person with myopia (short-sightedness) cannot focus on distant objects. Which corrective lens is used and why?

A glass lens has index n = 1.6. What is the speed of light in this glass? (c = 3.0 × 10^8 m/s)

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?

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 lens has power P measured in dioptres such that P = 1/f (f in metres). What is the power of a lens with focal length 0.25 m?

A beam of red light and a beam of blue light enter a glass prism at the same angle. Which statement is true about their angles of refraction in the glass?

A lens produces an image with magnification m = -2. What does this tell you about the image?

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

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

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