Question

A copper rod at 25°C is 1.5 m long.

How long would it take a sound to move through the rod from one end to another?

2.9×10−4 s

9.8×10−4 s

4.5×10−3 s

4.2×10−4 s

Speed of Sound Waves in Various Media
Medium m/s
Air (0°C 331
Air (20°C) 343
Helium (0°C) 972
Water (25°C) 1,493
Seawater (25°C) 1,533
Copper (25°C) 3,560
Iron 5,130

i think it would be D?

Answer 1

4.2*10^-4 is what i was thinking

Answer 2

Yes you are right, you need to use dimensional analysis and take the inverse of the speed

Answer 3

Yes, that is what I did!(: thanks for checking