If the current takes him downstream we must find the resultant vector of the velocities:
Then if the river is 3000 m-wide the swimmer will have to pass:
1.3520747 · 300 = 4056.14 m t = 4056.14 m : 1 m/s
a ) It takes
4056.15 seconds ( 1 hour 7 minutes and 36 seconds ) to cross the river.
b ) 0.91 · 3000 =
2730 mHe will be 2730 m downstream.
Desired operation: A + B = C; {A,B,C) are vector quantities.
<span>Issue: {A,B} contain error (measurement or otherwise) </span>
<span>Objective: estimate the error in the vector sum. </span>
<span>Let A = u + du; where u is the nominal value of A and du is the error in A </span>
<span>Let B = v + dv; where v is the nominal value of B and dv is the error in B </span>
<span>Let C = w + dw; where w is the nominal value of C and dw is the error in C [the objective] </span>
<span>C = A + B </span>
<span>w + dw = (u + du) + (v + dv) </span>
<span>w + dw = (u + v) + (du + dv) </span>
<span>w = u+v; dw = du + dv </span>
<span>The error associated with w is the vector sum of the errors associated with the measured quantities (u,v)</span>
Answer:
1070 Hz
Explanation:
First, I should point out there might be a typo in the question or the question has inconsistent values. If the tube is 40 cm long, standing waves cannot be produced at 42.5 cm and 58.5 cm lengths. I assume the length is more than the value in the question then. Under this assumption, we proceed as below:
The insert in the tube creates a closed pipe with one end open and the other closed. For a closed pipe, the difference between successive resonances is a half wavelength 
.
Hence, we have
.
The speed of a wave is the product of its wavelength and its frequency.
The answer is D) vibrate. vibrations are what cause sound. Consequently, this is why there is no sound in space, because there is no medium for the for which sound to travel
Answer;
D. ocean currents might change course.
Explanation;
Ocean currents are the directed movements of water in the ocean and can be caused by wind (for currents closer to the surface) and temperature, salinity, or density differences (currents deeper in the ocean). Ocean currents help to warm or cool certain parts of the earth by carrying warmer water northward or cooler water toward the equator.
Climate change can have a vast effect on ocean currents because of the change in temperature it causes, which results in change in ocean water temperatures and a subsequent distortion in current flow.
