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Grade 11Mechanics

a bomb at rest explodes into three fragments.two fragments fly off at right angles to each other.these two fragments:the one with mass 2kg moves with a speed of 12m/s,and the other onewith mass 1kg moves with 8m/s.the speed of the third fragment is 20m/s,then calculate its mass

Profile image of aadil
8 Years agoGrade 11
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1 Answer

Profile image of sourav mittal
8 Years ago
if the bomb is at rest , its velocity is 0 , hence its mommentumis 0
now , its explodes into 3 parts …
1st  part : mass=2kg, v1=-12 m/s( – sign is due to opposite direction , you can also take v1 and v2 +ve  and  v3 -ve)
2nd part : mass= 1kg; v2 =- 8m/s
3rd part : v3 = 20m/s
initially bomb was at rest , therefore its initial momentum =0;
as we know momtum remains conserved,therefore initial momentum = final momentum
0=2*-12+1*-8+m*20
32=20m
m=1.6kg