Two pulses, one of red light and one of ultraviolet radiation, leave the same point at the same time. They travel the same distance through a vacuum to a detector.
Which statement about their arrival is correct?
They arrive together because their speeds are equal despite their different frequencies.
They arrive together because their frequencies are equal despite their different wavelengths.
Ultraviolet arrives first because its higher frequency gives it a greater speed.
Red light arrives first because its longer wavelength gives it a greater speed.
84 exam-style questions on Edexcel GCSE Physics 5.2 The electromagnetic spectrum, covering 5.2.1 Electromagnetic waves and refraction in glass (core practical), 5.2.2 Groups of the electromagnetic spectrum, 5.2.3 Wavelength-dependent behaviour of EM waves, and 5.2.4 Velocities of EM waves in different substances. Each one has a worked solution and a mark scheme showing where the marks go.