Exploding Object Problem: Solving for the Speed of the Third Fragment

[shadowice]

Homework Statement

A 48.0-kg body is moving in the direction of the positive x-axis with a speed of 389 m/s when, owing to an internal explosion, it breaks into three pieces. One part, whose mass is 9.5 kg, moves away from the point of explosion with a speed of 385 m/s along the positive y axis. A second fragment, whose mass is 3.0 kg, moves away from the point of explosion with a speed of 413 m/s along the negative x axis. What is the speed of the third fragment? Ignore effects due to gravity.

M= 48kg
M1 = 9.5kg
M2= 3 kg
M3= 35.5 kg
Fnet = 0

Homework Equations

p=mv
m1v1+m2v2+m3v3=mv0

The Attempt at a Solution

been trying to do p = 48*389 = 18672
then 3*-413 +35.5 * Vx = 18672
then get vx of 560.87
then do vy = 9.5*385 + 35.5 vy = -103.02
then vx^2+ vy^2 = v3^2 and i get 551.33 and its not accepting

 

[AEM]

Homework Statement

A 48.0-kg body is moving in the direction of the positive x-axis with a speed of 389 m/s when, owing to an internal explosion, it breaks into three pieces. One part, whose mass is 9.5 kg, moves away from the point of explosion with a speed of 385 m/s along the positive y axis. A second fragment, whose mass is 3.0 kg, moves away from the point of explosion with a speed of 413 m/s along the negative x axis. What is the speed of the third fragment? Ignore effects due to gravity.

M= 48kg
M1 = 9.5kg
M2= 3 kg
M3= 35.5 kg
Fnet = 0

Homework Equations

p=mv
m1v1+m2v2+m3v3=mv0

The Attempt at a Solution

been trying to do p = 48*389 = 18672
then 3*-413 +35.5 * Vx = 18672
then get vx of 560.87
then do vy = 9.5*385 + 35.5 vy = -103.02
then vx^2+ vy^2 = v3^2 and i get 551.33 and its not accepting

Remember the following:

(1) Momentum before = Momentum After

(2) Momentum is a vector quantity so the momentum in the x direction must be conserved and separately momentum in the y direction must be conserved.

(3) Consequently the third piece moves in such a way as to guarantee number (2)

 

[shadowice]

figured out my error can delete this topic or close whichever you do