Question

The following table lists the speed of sound in various materials. Use this table to answer the question.

Substance
Speed (m/s)
Glass
5,200
Aluminum
5,100
Iron
4,500
Copper
3,500
Salt water
1,530
Fresh water
1,500
Mercury
1,400
Hydrogen at 0°C
1,284
Ethyl Alcohol
1,125
Helium at 0°C
965
Air at 100°C
387
Air at 0°C
331
Oxygen at 0°C
316



How long would it take for a sound impulse to travel through an aluminum rod 25 kilometers long?
0.0049 sec
0.071 sec
4.9 sec
0.14

Answer 1

4.9sec

Step-by-step explanation:

Answer 2

Answer: Time taken by a sound impulse to travel through an aluminum rod 25 kilometers long is 4.9 seconds.

Solution:

Length of aluminium rod = 25 km = 25000 m (1 km=1000 m)

Time taken by sound to travel through aluminium = 5100 m/s (from the table given)

`speed=(distance)/(time)=\frac{25000 m}{\text{time taken}}`

time taken =
`(distance)/(speed)=(25000 m)/(5100 m/s)=4.9019 seconds\approx 4.9 seconds`

Hence, the correct option is 4.9 seconds.