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Ms.bio
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I know its physics but can someone help me out on this? Please...What is the resultant momentum of a system of two particles with these masses and velocities: 3.75kg m/s moving North and 4.2 kg moving Northwest at 2.3 m/s?
 2 years ago
 2 years ago
Ms.bio Group Title
I know its physics but can someone help me out on this? Please...What is the resultant momentum of a system of two particles with these masses and velocities: 3.75kg m/s moving North and 4.2 kg moving Northwest at 2.3 m/s?
 2 years ago
 2 years ago

This Question is Closed

zer0net Group TitleBest ResponseYou've already chosen the best response.0
is the 3.75kg also traveling at 3.75m/s?
 2 years ago

Ms.bio Group TitleBest ResponseYou've already chosen the best response.0
wait I forgot...3.75 is moving at 5.6 m/s
 2 years ago

dmancine Group TitleBest ResponseYou've already chosen the best response.0
I don't totally understand the concept of the question, but it might just be that you need to add the two momentum vectors together. Step 1: draw a picturedw:1318046019675:dw
 2 years ago

dmancine Group TitleBest ResponseYou've already chosen the best response.0
Now calculate the momemtum vectors.dw:1318046160525:dw Now add the two vectors.
 2 years ago

zer0net Group TitleBest ResponseYou've already chosen the best response.0
p=mv P1=3.75*5.6=21N P2=4.2*2.3=9.66NW since its NW you know its 45degrees, so find normal vectors at that angle 9.66cos45 = 5.07 (i dont have calc) so your momentum will be 21N+5.07N = 26.07N
 2 years ago

Ms.bio Group TitleBest ResponseYou've already chosen the best response.0
yes i need to add the momentum together but i can't get how. I thought I have to use law of sines and cosines but I am not confident dealing with it.
 2 years ago

zer0net Group TitleBest ResponseYou've already chosen the best response.0
or you can also calculate NW vector based on your N vector and have a resulting momentum in direction of NW rather than N, however both answers should be correct.
 2 years ago

dmancine Group TitleBest ResponseYou've already chosen the best response.0
To add vectors together they need to be in rectangular form, not polar form. If you have a vector in polar form as (r, theta), then its rectangular coordinates are (r cos(theta), r sin(theta)).
 2 years ago

zer0net Group TitleBest ResponseYou've already chosen the best response.0
still confused?
 2 years ago

dmancine Group TitleBest ResponseYou've already chosen the best response.0
You said you got: In respect to the other post I used Law of Sines and Cosines and got an answer of 17.26kgm/s at 35.45 degree Nof W
 2 years ago

dmancine Group TitleBest ResponseYou've already chosen the best response.0
dw:1318053871126:dw When you add vectors together, the result will be the diagonal of the parallelogram they create. So, the result has to be between the two vectors. Where is your answer vector pointing?
 2 years ago

Annand Group TitleBest ResponseYou've already chosen the best response.0
Let P=9.66 Q=21 x=angle between the vectors which is 45 then magnitude of resultant is \[R=\sqrt{P^2+Q^2+2PQcos(x)}\]
 2 years ago

Annand Group TitleBest ResponseYou've already chosen the best response.0
dw:1318072907791:dw
 2 years ago

Annand Group TitleBest ResponseYou've already chosen the best response.0
and angle with respect to Ndirection can be obtained from: \[R\times\cos\theta=Q+P\times\cos45\]
 2 years ago
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