What is the speed of water waves?

In summary, we discussed the calculation of speed and wavelength for water waves and sound waves. We used the formula v=dt to find the speed and d=vt to find the wavelength. It is important to read the questions carefully and pay attention to units when solving physics problems.
  • #1
jai6638
263
0
Water waves in a shallow dish are 6 cm long. At one point, the water oscillates up and down at a rate of 4.8 oscillations per second.

A. what is the speed of water waves?


Do i have to just use the formula V=(lambda)(f) = (.06)(4.8) ??


thanks
 
Last edited:
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  • #2
That's all there is to it. (Don't forget units.)
 
  • #3
great thanks.. had another question:

Water waves in a lake travel 4.4 m in 1.8 s. THe period of oscillation is 1.2s.

A. What is the speed of water waves?
b. what is their wavelenght?

Answer A: v=(lambda) / (time)

what would i use as time here? 1.8 s or 1.2 s? why?

thanks
 
  • #4
also , a sound wave of wavelength .70m and velocity 330m/s is produced for .50s.

A. How many complete waves are emitted in this time interval?
Do i have to calculuate frequency for this?

b. after .50s, how far is the front of the wave from the sourece of the sound?

wont it be .70m as its the wavelength?

thanks
 
  • #5
jai6638 said:
great thanks.. had another question:

Water waves in a lake travel 4.4 m in 1.8 s. THe period of oscillation is 1.2s.

A. What is the speed of water waves?
b. what is their wavelenght?

Answer A: v=(lambda) / (time)

what would i use as time here? 1.8 s or 1.2 s? why?

thanks
To answer these questions, you first have to calculate the speed of the wave using the simple formula v=dt. (use 4.4m and 1.8s)
To find the period, find the distance the wave travels in 1.2s (using the speed you calculated in A.)
 
  • #6
jai6638 said:
also , a sound wave of wavelength .70m and velocity 330m/s is produced for .50s.

A. How many complete waves are emitted in this time interval?
Do i have to calculuate frequency for this?

b. after .50s, how far is the front of the wave from the sourece of the sound?

wont it be .70m as its the wavelength?

thanks
To answer A., you have to calculate the frequency.
To answer B., you cannot say the answer is .50s, since the question is not telling you it travels .70m in 0.50s. It is simply telling you that a wave HAVING a wavelength of .70m is "produced" for 0.50s. You just have to use the velocity (330m/s) and the time (0.50s) to calculate the distance it travels in 0.50s.

Always read the problem carefully before attempting to solve it.
 
  • #7
christinono said:
To answer these questions, you first have to calculate the speed of the wave using the simple formula v=dt. (use 4.4m and 1.8s)
To find the period, find the distance the wave travels in 1.2s (using the speed you calculated in A.)

so i get

V = (4.4)(1.8)= 7.92 m/sec
D = (1.2)(7.92) = 9.5 m
T = 9.5/ ( 1.2) (4.4 ) = 1.8 s !

damn .. I am gettin the same T as in the question...?.. what am i doing wrong here

thanks ..

To answer A., you have to calculate the frequency.
To answer B., you cannot say the answer is .50s, since the question is not telling you it travels .70m in 0.50s. It is simply telling you that a wave HAVING a wavelength of .70m is "produced" for 0.50s. You just have to use the velocity (330m/s) and the time (0.50s) to calculate the distance it travels in 0.50s.

Always read the problem carefully before attempting to solve it.


thanks
 
  • #8
anyone?...
 
  • #9
jai6638 said:
so i get

V = (4.4)(1.8)= 7.92 m/sec
D = (1.2)(7.92) = 9.5 m
T = 9.5/ ( 1.2) (4.4 ) = 1.8 s !

damn .. I am gettin the same T as in the question...?.. what am i doing wrong here

thanks ..




thanks
I don't quite get what you did...Don't you need to calculate the frequency first?
 
  • #10
christinono said:
I don't quite get what you did...Don't you need to calculate the frequency first?

a) ok so finding the speed is simply the function of multiplying 4.4 and 1.8 right? ( since v = (lambda)(f) )



B) V = Lambda / Time

Lambda = (V) (time )
= (4.4)(1.8)(1.2)
= 9.5 m

is thta correct?

why would i need to find the frequency?
 
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  • #11
Which question are you talking about?
This one:
Water waves in a lake travel 4.4 m in 1.8 s. THe period of oscillation is 1.2s.

A. What is the speed of water waves?
b. what is their wavelenght?

or this one?:
also , a sound wave of wavelength .70m and velocity 330m/s is produced for .50s.

A. How many complete waves are emitted in this time interval?
 
  • #12
talkinga bout :

Water waves in a lake travel 4.4 m in 1.8 s. THe period of oscillation is 1.2s.

A. What is the speed of water waves?
b. what is their wavelenght?
 
  • #13
jai6638 said:
talkinga bout :

Water waves in a lake travel 4.4 m in 1.8 s. THe period of oscillation is 1.2s.

A. What is the speed of water waves?
b. what is their wavelenght?
OK. To find the speed, just use the formula d=vt (d=4.4 and t=1.8). To find the wavelength, just find the distance the wave travels in 1.2 seconds (using the same formula).

Nothing to it! :biggrin:
 
  • #14
wow! that was stupid of me... lol...

thanks much :)
 
  • #15
Physics has its way of seeming so hard at times... :tongue2:
 
  • #16
christinono said:
Physics has its way of seeming so hard at times... :tongue2:

lol.. so true :)
 

1. What is the speed of water waves?

The speed of water waves depends on various factors such as the depth of the water, the wavelength of the wave, and the presence of any obstacles. Generally, shallow water waves have a speed of around 1.25 times the square root of the depth of the water in meters. For example, if the depth is 10 meters, the speed of the wave would be approximately 12.5 meters per second.

2. How does the speed of water waves compare to other types of waves?

The speed of water waves is relatively slower compared to other types of waves such as sound waves or electromagnetic waves. For example, the speed of sound waves can be as high as 343 meters per second in air, while the speed of water waves is typically around 1-2 meters per second.

3. Does the speed of water waves change in different bodies of water?

Yes, the speed of water waves can vary in different bodies of water depending on their characteristics. For instance, the speed of waves in the ocean can differ from the speed of waves in a lake or a river due to differences in depth and water density.

4. How does wind affect the speed of water waves?

Wind can significantly affect the speed of water waves. Stronger winds can create larger and faster waves, while calmer winds may result in smaller and slower waves. Additionally, the direction and speed of the wind can also impact the direction and speed of the waves.

5. Can the speed of water waves be measured?

Yes, the speed of water waves can be measured using various instruments such as wave buoys, wave gauges, and radar systems. These instruments can record the height and speed of waves, providing valuable data for studying ocean currents and weather patterns.

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