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Two balls collide elastically the balls have masses of 3.4 and 5.7, if the 3.4 ball is moving at 10.5 m/s toward the other ball and the 5.7 kg ball is moving with a speed of 6.7 what are the final speeds of the balls?

User LiamD
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1 Answer

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Answer: The final speed of the balls will be 8.12m/s

Step-by-step explanation:

For least collision of bodies, both momentum and kinetic energy is conserved.

According to Law of conservation of energy,

The sum of momentum of the objects before collision is equal to the sum of their momentum after collision. Note that the objects will move with a common velocity after impact.

Let m1 and m2 be the masses of the objects

u1 and u2 be their velocities before impact

v be their common velocity after impact

Since momentum is mass × velocity

Mathematically,

m1u1 + m2u2 = (m1+m2)v

Given m1= 3.4kg m2 = 5.7kg u1 = 10.5m/s u2 = 6.7m/s v = ?

Substituting this values in the formula, we have

3.4(10.5)+5.7(6.7) = (3.4+5.7)v

35.7+38.19 = 9.1v

73.89 = 9.1v

V = 73.89/9.1

V= 8.12m/s

User Bas Van Ommen
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