An asteroid is discovered heading straight toward Earth at 15 km/s. An international team manages to attach a giant rocket engine to the asteroid. The rocket fires for 10 min, after which the asteroid is moving at 28[tex]\circ[/tex] to its original path at a speed of 19 km/s.(adsbygoogle = window.adsbygoogle || []).push({});

Find its average acceleration (a_{x}, a_{y}) in m/s^{2}.

I first began by using the equation a^{2}= b^{2}+ c^{2}-2bc(cos[tex]\alpha[/tex]) where b is 15 km/s and c is 19 km/s.

a^{2}= 225 + 361 - 570(cos28[tex]\circ[/tex])

a^{2}= 82.7 km/s

9.1 km/s m= [tex]\Delta[/tex]v

a= 9.1 / 600 = .0152 km/s^{2}= 15.2 m/s^{2}

The answer is [tex]r\hat{}[/tex] = (3.0[tex]i\hat{}[/tex] + 15 [tex]j\hat{}[/tex]) m/s^{2}.

I am unsure as to whether or not I have done this correctly because I do not know where to go from here. My professor gave use this hint for this problem:

The asteroid is initially going in the +x direction! From the given initial and final

velocities, find [tex]\Delta[/tex]v_{x}and [tex]\Delta[/tex] v_{y}. Use a_{x}= [tex]\Delta[/tex]v_{x}/[tex]\Delta[/tex]t and a_{y}= [tex]\Delta[/tex]v_{y}/[tex]\Delta[/tex]t

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# Homework Help: Assistance needed with vector velocity problem, please

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