Short answerEasy1 mark
3(a)
The wave lengths for the light of red and blue colours are nearly 7.8 × 10–7 m and 4.8 × 10–7 m respectively.
Which colour has the greater speed in a vacuum ?
Topic: Electromagnetic spectrum / scattering
Previous-year question practice database
Answer
Exam answer
Both have the same speed in vacuum.
Explanation
All colours travel at c in vacuum.
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