How Far Did the Parachutist's Impact Occur from the Swimmer?

AI Thread Summary
A swimmer observes a parachutist's impact and hears the sound twice, once through water and once through air, with a 1.0-second delay. The speeds of sound in air and water are 340 m/s and 1400 m/s, respectively. The problem involves calculating the distance from the swimmer to the splash point using the time it takes for sound to travel through both mediums. The equations derived show that the difference in travel times equals 1 second, leading to a calculated distance of approximately 450 meters. The discussion emphasizes solving the rate x time = distance equation to find the correct distance.
whatwhat11
Messages
14
Reaction score
0
A swimmer sees a parachutist hit the water and hears the impact twice, once through the water and the second time through the air, 1.0 s later. How far from the swimmer did the impact occur?
Vs air = 340 m/s Vs water = 1400 m/s the answer is 450m

I don't understand what to do :confused:
 
Physics news on Phys.org
whatwhat11 said:
A swimmer sees a parachutist hit the water and hears the impact twice, once through the water and the second time through the air, 1.0 s later. How far from the swimmer did the impact occur?
Vs air = 340 m/s Vs water = 1400 m/s the answer is 450m

I don't understand what to do :confused:

This is a straightforward rate x time = distance (r t = d) problem.

Let d = distance from swimmer to splash point.

In terms of d, how much time does the sound take to get from the splash point to the swimmer in air?

In terms of d, how much time does the sound take to get from the splash point to the swimmer in water?

In terms of d, what is the difference between these two times?

(Actually, the answer is not 450m, it's only 449m, but who's counting?)
 
Chestermiller said:
This is a straightforward rate x time = distance (r t = d) problem.

Let d = distance from swimmer to splash point.

In terms of d, how much time does the sound take to get from the splash point to the swimmer in air?

In terms of d, how much time does the sound take to get from the splash point to the swimmer in water?

In terms of d, what is the difference between these two times?

(Actually, the answer is not 450m, it's only 449m, but who's counting?)

Vsound in air= (340)(2)
=680m

V sound in water = (1400)(1)
=1400

1400-680
doesn't equal 450m or 459m
 
whatwhat11 said:
Vsound in air= (340)(2)
=680m

V sound in water = (1400)(1)
=1400

1400-680
doesn't equal 450m or 459m

Hu?

The answer to my first question was: the amount of time it takes for the sound to travel through the air from the splash to the swimmer is d/340 seconds

The answer to my second question was: the amount of time it takes for the sound to travel through the water from the splash to the swimmer is d/1400 seconds

The answer to my third question was: the difference between these two times is (d/340) - (d/1400) =1 second

Are you able to solve this equation for the distance d? If so, what do you get for d?
 
Thread 'Voltmeter readings for this circuit with switches'

Thread 'Voltmeter readings for this circuit with switches'

TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
View full post »
Thread 'Correct statement about a reservoir with an outlet pipe'

Thread 'Correct statement about a reservoir with an outlet pipe'

The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
View full post »

Similar threads

How far did the parachutist fall before hitting the water?
Replies
5
Views
2K
What angle should a swimmer aim to land directly across the starting position?
Replies
6
Views
2K
Audio interference of sound waves from two speakers
Replies
19
Views
4K
Waves: Calculate the sound intensity from two speakers
Replies
3
Views
3K
Frequency for resonance to occur
Replies
33
Views
3K
Doppler effect and beat frequency
Replies
3
Views
3K
Speed of Sound using a Resonant tube
Replies
12
Views
4K
Speed of bowling ball involving speed of sound
Replies
7
Views
5K
Sources of Error in a Speed of Sound Experiment
Replies
3
Views
22K
Sound Interference Problem -- Observer moving between two speakers
Replies
3
Views
4K

Hot Threads

Recent Insights

Back
Top