Herschel Ritter

Question 1

How did Herschel discover infrared

Answer 1

used white light from the Sun
• glass prism
• produced a visible spectrum

used a thermometer to measure the temperature of different colours of the visible spectrum
• temperature increased towards the red end
• temperature increased more past the red end of the
spectrum.
• temperature rise was due to invisible rays named infrared

Question 2

How did Ritter discover UV

Answer 2

used white light from the Sun
• glass prism
• produced a visible spectrum

used silver chloride on paper this slowly turns black in visible light.
• silver chloride turned black faster as the paper was put at the violet end of the spectrum
• beyond the violet the silver chloride turned black even more rapidly
• due to the presence of invisible rays (originally called chemical rays) now called ultraviolet