Author Question: Explain why, when someone across the room pierces a can of coffee with a can opener, you hear the ... (Read 56 times)

darbym82 · **on:** Jul 29, 2018

Explain why, when someone across the room pierces a can of coffee with a can opener, you hear the sound of the can being pierced before you smell the aroma of the coffee.

What will be an ideal response?

Question 2

A person with normal eyesight uses a converging lens of focal length 10 cm. He holds the lens close to his eyes to finish an engraving job. What is the magnifying power of the lens?

A) 3.5
B) 4.5
C) 6.5
D) 7.5
E) 8.5

234sdffa · **Reply #1 on:** Jul 29, 2018

Answer to Question 1

Sound is carried by compressions and rarefactions of the air; it does not rely on individual molecules to carry it. Individual molecules of the compounds that make up coffee carry the aroma of coffee. Thus we are comparing the time that it takes sound to propagate a certain distance against the time that it takes some of the molecules of these compounds to work their way across the room, while moving in random directions and undergoing collisions with other molecules.

Answer to Question 2

A