HighMarks

Light propagation — KCSE Physics

KCSE Physics · 110 practice questions · 10 syllabus objectives

36 easy37 medium37 hard

What You'll Learn

Key learning outcomes for this topic, aligned to the KNEC KCSE syllabus.

Apply magnification formula M = h_i/h_o = v/u to solve pinhole camera problems

State that light travels in straight lines (rectilinear propagation) and apply this to explain shadows and eclipses

Describe the formation of an image in a pinhole camera and relate image size to object size and distances

State the speed of light in a vacuum (3 × 10⁸ m/s) and convert between frequency and wavelength using v = fλ

State that light travels in straight lines and describe experiments to demonstrate rectilinear propagation

Define umbra and penumbra; explain shadow formation from point and extended sources

Describe the formation of solar and lunar eclipses including annular eclipses

Describe the pinhole camera, sketch ray diagrams, and state properties of the image formed

Explain effects of changing pinhole diameter and camera length on the image

Light propagation

Sample Questions

Try 3 questions free. Sign up to access all 110 questions with full marking schemes.

1
easySHORT ANSWER3 marks

A pinhole camera is set up so that the object is 50 cm away from the pinhole and the image distance is 200 cm. Calculate the magnification produced by the camera. (3 marks)

View Marking Scheme
Part (a) — 3 marks
M = v/u = 200 cm / 50 cm (1 mk)
M = 4 (1 mk)
The magnification is 4, meaning the image is four times larger than the object (1 mk)
2
easySHORT ANSWER2 marks

State the magnification formula used to describe the relationship between the height of the image and the height of the object in a pinhole camera. (2 marks)

View Marking Scheme
Part (a) — 2 marks
M = hᵢ/hₒ = v/u, where M is magnification, hᵢ is height of image, hₒ is height of object, v is image distance, and u is object distance (2 mks)
3
easySHORT ANSWER2 marks

Name two effects of increasing the length of a pinhole camera on the image produced. (2 marks)

View Marking Scheme
Part (a) — 2 marks
The image becomes larger (magnified) as the distance increases (1 mk)
The image may become clearer (sharper) due to better light convergence (1 mk)
4

State two properties of the image produced by a pinhole camera when an object is placed at a distance greater than the focal length. (2 marks)

+107 More Questions

Sign up free to access all 110 questions with marking schemes, track your progress, and get personalised recommendations.

Why Practise Light propagation?

KNEC Aligned

Questions match the KCSE syllabus objectives and exam format exactly.

Detailed Marking Schemes

Every answer shows exactly what examiners award marks for.

Track Your Mastery

See your score improve as you practise and identify remaining gaps.

Master Light propagation for KCSE

Sign up free to unlock all 110 questions, track your progress, and get a personalised study plan for Physics.