0:00
Hi there.
00:01
So for this problem we have a stream which is 2 .72 meters long and has a mass that is also given of 263 grams.
00:23
And there is a tension in the stream which is equal to 36 .1 newton.
00:34
And for this we are asked about what must be the frequency of traveling waves that has an amplitude of 7 .7 millimeters in order that the average transmitted power is equal to 85 .5 watts.
01:14
Now, from this we can obtain the linear mass density because we know that the linear mass density is the mass in kilograms, so we transform this value into kilograms and we know that that is 0 .263 kilograms over the length of this rod or this string in this case.
01:43
So we will have 0 .2163 kilograms over the length of this rod, 263 kilograms over the length of this which is 2 .72 meters so from this we obtain a linear mass density of 9 .669 times 10 to the minus 2 kilograms per meter.
02:11
Now the wave of speed can be obtained from the following equation, we know that this bit in a stream is equal to the square root of the force that is being applied to this stream, that in this case is the tension over the linear density.
02:31
So we just simply substitute the values in here.
02:34
We have the square root of 36 .1 mutons over the linear density, the value that we just have obtained.
02:51
And from this we obtain a speed of the waves in this string.
02:58
Let me move this to the left.
03:01
Then this speed is equal to 19 .32 meters per second.
03:15
And now we use the following equation.
03:19
That states that the average power is equal to 1 over 2 the linear density...