# Land in Focus – Basics of Remote Sensing

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Home Forums Land in Focus – Basics of Remote Sensing Electromagnetic Waves and their Spectrum

• # Electromagnetic Waves and their Spectrum

Posted by on September 30, 2021 at 3:16 pm
6 Members · 5 Replies
• 5 Replies
• ### Helena van Mierlo

Member
June 29, 2023 at 1:49 pm

Hi, thanks for this great material. There is a mistake in the first quiz. The distance between the peak and the trough is not the amplitude, but 2x the amplitude. Thank for correcting this.

• ### Janna Lumiruusu

Member
September 22, 2023 at 6:56 pm

I noticed the same mistake. It’s still not corrected.

• ### Beenzu M Muzyamba

Member
November 7, 2023 at 7:47 pm

I thought I was crazy when I got it wrong.

• ### Alvaro Sedano

Member
November 6, 2021 at 8:58 pm

The assertion “All three are related mathematically such that if you know one, you can calculate the other two using this equation: c=lambda * freq” is wrong.

If you know 2 of these 3, you can calculate the other one.

Thank you.

• ### Kai Heckel

Member
November 8, 2021 at 8:26 am

Dear Alvaro,
thank you for your hint, that was a typo, and exactly what we meant :).
We just corrected it.