<p>A ship is steaming at 30km/hr S 45 degrees W. At that moment, 50 kn due south of it, a submarine heading N 30 degrees W spots it. At what velocity must a torpedo from the submarine travel if it is to strike the ship.</p>
<p>-Any help would be appreciated.</p>
<p>Its just a triangle with the straight vertical line as 50, the top angle is 45 degree, the bottom angle is 30 degrees, making the angle to the left 180-45-30 = 105 degrees. The top left side is 30t and the bottom to that left angle is unknown velocity times t. So you can use law of sins. So sin 105 / 50 = sin30 / whatever and that whatever = 30km/h *t hrs. So you can solve for t. And then you store that. Now do law of sins to the last angle 45 degrees and you get the length that the torpedo has to go. Divide that length by the time t to get a speed.</p>
<p>Or you can say that 30 sin45 = Vsin30 and that V is the velocity of the torpedo. It is basically taking the vectors of movement west and setting them equal to eachother. If you had to find t use the top way otherwise just do this.</p>