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mathematics-- relative velocity
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no matter how i think, i just can't picture the solution so i hope someone can help me... if possible, can u please include a picture of the triangle to draw (with the appropriate labels)... thanks... 1. At a given instant, an airship is moving due north with a speed of 6m/s. A helicopter which is 500m due east of the airshop flies at a speed of 12m/s and steers on a bearing X in order to intercept the airship. Find (a) the value of X (b) the time that elapses before interception. Answer: (a)30 degrees (b)48s 2. Two particles, A and B, are 50m apart with A due north of B. Particle A is travelling at 10m/s in a direction 075 degrees and B is travelling at Vm/s in a direction 0.15 degrees. (a) Given that V=20, find (i) the magnitude and direction of the velocity of B relative to A, (ii) the time taken for B to be due west of A. (b) Given that B collides with A, find (i) the value of V, (ii) the time taken for B to collide with A. Answer: (a) (i) 17.3m/s, 345 degrees (ii) 2.99s (b) (i) 37.3m/s (ii) 1.49s |
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Re: mathematics-- relative velocity
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 Is this clear enough? Here, "t" is the time until the aircrafts intercept each other... The coloured balls are the ships. If you don't specify from where you're counting the degrees in the second problem, it's impossible to solve... Also, 0.15 degrees? Ain't that too small? Well, this problem seems very similar to the first one, so give it another try after checking the first resolution... Hope the image is clear enough. (so yeah, I don't have anything else to do but other people's homework.)
"From East Middle School, Suzumiya Haruhi.
I'm have no interest in ordinary humans. If there are any aliens, time travelers, sliders or espers here, then come join me."
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Re: mathematics-- relative velocity
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1st Q. K is right, you can prove it via simultaneous equations because the copter will always travel twice the length of the ship. 2nd Q. it is enough as all bearings are taken from N and start clockwise. Does it match with the answers though? i'm not sure, should look something like this:   |