1. 1
   A student uses a convex lens in a simple camera model to focus light from a distant object onto a screen.

   (a)

   What type of image is formed on the screen?

   [1 mark]

   • AA virtual, upright image
   • BA real, inverted image
   • CA real, upright image
   • DA virtual, magnified image only

   (b)

   What happens to rays of light travelling parallel to the axis of the convex lens as they pass through it?

   [1 mark]

   • AThey spread further apart
   • BThey continue in exactly the same direction
   • CThey converge and meet at the principal focus
   • DThey are completely reflected back towards the source

   (c)

   Describe what is meant by the principal focus of the convex lens, and state how the focal length is defined.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   An optician examines a patient using a concave lens to help correct short-sightedness (myopia), and compares this with a hand-held magnifying glass, which uses a convex lens with the object placed closer to the lens than its focal length.

   (a)

   What type of image is always produced by the concave lens used in the patient's glasses?

   [1 mark]

   • AA virtual image
   • BA real image only
   • CAn inverted, magnified image
   • DAn image that can be projected onto a screen

   (b)

   When the convex lens of the magnifying glass is held with the object closer to the lens than its focal length, what type of image is seen?

   [1 mark]

   • AA real, inverted, diminished image
   • BA virtual, inverted, magnified image
   • CA real, upright, diminished image
   • DA virtual, upright, magnified image

   (c)

   The magnifying glass forms an image of a 4 mm tall object that appears 12 mm tall. Calculate the magnification produced.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A fashion designer is choosing fabric colours under different types of shop lighting, including white light and lighting from a lamp that produces only red light, to see how garments will appear to customers.

   (a)

   Explain why a blue garment appears blue when viewed in white light.

   [3 marks]

   (b)

   Explain what colour the blue garment would appear to be under the lamp that produces only red light.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A greenhouse designer is choosing between clear glass panels and coloured plastic filter panels for different sections of a greenhouse, and is also considering the effect of curved glass skylights that focus sunlight like a convex lens.

   (a)

   Describe the difference between transparent, translucent and opaque materials, and explain how a red-coloured filter affects white light passing through it.

   [6 marks]

   (b)

   Evaluate the risks and benefits of using curved glass skylights, which act as convex lenses, in the greenhouse design, referring to how a convex lens forms an image and can concentrate light energy.

   [6 marks]

   Total for question 4: 12 marks

End of questions