Why can people hum certain high/low notes but can’t sing them?

Question

Why can people hum certain high/low notes but can’t sing them?

In: Biology

Answer 1

Certain vowel sounds stress or tighten the vocal cords more than others. For example, singing a high pitched “ee” sound is harder than a high pitched “oh” sound. When you hum, your vocal cords don’t need to differentiate vowel sounds and instead produce sound in a more relaxed state.