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bgaspar00
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A grenade of mass 10 kg explodes into three pieces in the same plane, two of which, A (5.0 kg) and B (2.0 kg), move off as shown. Calculate the velocity of the 3.0 kg third piece, C.
I cannot show all of my work becuz it is basically just a sketch of what the diagram would look like, then drawing vectors and so on. However, i cannot get the right answer.
So here's the diagram it shows...
http://www.cbv.ns.ca/rv/physics/Physics12/BLM10-3.pdf
Δp = 0 where pi = 0
pix = pfx and piy = pfy
p1’
p1y’ = Cos30(5.0 kg (100.0 m/s))
= 433.013 kgm/s
p1x’ = Sin30(5.0(100m/s))
= 250
p2y’ = cos20 (2kg)(200 m/s)
= cos20 ( 400 kgm/s)
p2x’ = sin20 (400 kgm/s)
p1x’ + p2x’ + p3x’ = 0
500 + (- sin 20 (400 kgm/s)) + p3x’ = 0
p3x’ = 363.192 kgm/s
p1y’ + p2y’ + p3y’ = 0
500 kgm/s + (- cos 20(400 kgm/s)) + p3y’ = 0
p3y’ = 124.123kgm/s
p3 is found by resolving p3x’ and p3y’
p3x’
p3y’
p3
θ
p3^2 = [363.192kgm/s]2
+[124.123 kgm/s]2
|p3| = 383.816 kgm/s
θ = tan-1 [(124.123kgm/s)/(363.192kgm/s)]
= 19 degrees? wtf v3 = p3/m3
v3 = 383.816kgm/s/(3kg)
v3 = 128 m/s
This is completely wrong the answer is suppose to be V3= 128.92 m/s (S 82 E) or something...soo where did i go wrong? and is there an easier wayyyyy!??
I cannot show all of my work becuz it is basically just a sketch of what the diagram would look like, then drawing vectors and so on. However, i cannot get the right answer.
So here's the diagram it shows...
http://www.cbv.ns.ca/rv/physics/Physics12/BLM10-3.pdf
Δp = 0 where pi = 0
pix = pfx and piy = pfy
p1’
p1y’ = Cos30(5.0 kg (100.0 m/s))
= 433.013 kgm/s
p1x’ = Sin30(5.0(100m/s))
= 250
p2y’ = cos20 (2kg)(200 m/s)
= cos20 ( 400 kgm/s)
p2x’ = sin20 (400 kgm/s)
p1x’ + p2x’ + p3x’ = 0
500 + (- sin 20 (400 kgm/s)) + p3x’ = 0
p3x’ = 363.192 kgm/s
p1y’ + p2y’ + p3y’ = 0
500 kgm/s + (- cos 20(400 kgm/s)) + p3y’ = 0
p3y’ = 124.123kgm/s
p3 is found by resolving p3x’ and p3y’
p3x’
p3y’
p3
θ
p3^2 = [363.192kgm/s]2
+[124.123 kgm/s]2
|p3| = 383.816 kgm/s
θ = tan-1 [(124.123kgm/s)/(363.192kgm/s)]
= 19 degrees? wtf v3 = p3/m3
v3 = 383.816kgm/s/(3kg)
v3 = 128 m/s
This is completely wrong the answer is suppose to be V3= 128.92 m/s (S 82 E) or something...soo where did i go wrong? and is there an easier wayyyyy!??