CourseCourseConceptConceptDocsDocuments

IB Physics SL C 3 7 Path Difference Questions

Practise IB Physics SL C.3.7 by calculating path differences and deciding when waves produce bright maxima or dark minima.

Syllabus
First assessment 2025
Course
Physics SL
Level
SL

Exam points

  • Calculate path difference and compare it with integral or half-integral wavelength conditions.
  • Explain how path difference creates constructive or destructive interference at a point.
  • Use path-difference reasoning for light, sound or microwave interference evidence.

Learn this topic

Study C.3.7—Path difference conceptsOpen the corresponding Concept lesson for explanations, examples and exam connections.

IB Physics SL C 3 7 Path Difference Questions question 1

[Maximum number: 1]

This question is about interference.

Light from a laser is incident on two identical parallel slits. The light from the two slits produces a fringe pattern on a screen.

Figure for Question IB Physics SL C 3 7 Path Difference Questions question 1 — IB Physics SL

A central bright fringe is produced at C . The next bright fringe is produced at A . There is a dark fringe at B .

The distance from the two slits to the screen is 1.5 m . The distance BC is 1.8 mm and the distance between the slits is 0.30 mm .

State the path difference, in metres, between the waves that meet at B .

All question bank results loaded