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8. A 2kg object explodes and divides into three pieces, one piece has a mass of 800g and has a velocity of [30] m/s, a second piece has a mass of 500g and has a velocity of [520] m/s. What is the velocity of the third mass?​

User Federer
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1 Answer

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Answer:

v3 = 0 gm/s / 700g

Step-by-step explanation:

To solve this problem, you need to use the principle of conservation of momentum, which states that the total momentum of a system remains constant unless acted upon by an external force. In this case, the total momentum of the system (the 2kg object before it explodes) is equal to the sum of the momenta of the three pieces after the explosion.

You can calculate the momentum of each piece by multiplying its mass by its velocity:

P1 = 800g * 30 m/s = 24,000 gm/s

P2 = 500g * 520 m/s = 260,000 gm/s

The total momentum of the system is the sum of these two momenta:

Ptotal = P1 + P2 = 24,000 gm/s + 260,000 gm/s = 284,000 g*m/s

The third piece has a mass of 2kg - 800g - 500g = 700g. We can use the conservation of momentum equation to find its velocity:

Ptotal = (700g * v3) + (800g * 30 m/s) + (500g * 520 m/s)

v3 = (Ptotal - (800g * 30 m/s) - (500g * 520 m/s)) / 700g

v3 = (284,000 gm/s - (800g * 30 m/s) - (500g * 520 m/s)) / 700g

v3 = (284,000 gm/s - 24,000 gm/s - 260,000 gm/s) / 700g

v3 = (284,000 - 24,000 - 260,000) gm/s / 700g

v3 = 0 gm/s / 700g

The velocity of the third mass is 0 m/s.

Hope this helps.

User Barshopen
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