# Hello Sound fans! Listen to Sydney!

Suppose your friend lives in Sydney, Australia, and today the Indian Prime minister, Narendra Modi, is about to deliver a speech in the Opera House. Your friend has reserved a seat 20 meters from the microphone. You are listening to the same speech on the radio in Mumbai, roughly 10,000 km from Sydney.

Suppose the time it takes the sound to reach you is $$t_\textrm{radio}$$ and the time is takes to reach your friend is $$t_\textrm{live}$$. How much faster the sound reach you, compared to your friend (i.e. find $$t_\textrm{live}/t_\textrm{radio}$$)?

Details and Assumptions:

• Take the speed of sound to be $$300 \text{ m/s}$$.
• The speed of radio waves is $$300,000 \text{ km/s}$$.
×