Elastic collision, 2 objects collide.

AI Thread Summary
In an elastic collision scenario, an object with a mass of 9.4 kg moving east at 15.3 m/s collides with a stationary object, resulting in the first object recoiling at -5.3 m/s. The initial calculation for the mass of the second object was proposed as 35.9 kg, but this was identified as incorrect. The formula used for the calculation was noted to have missing parentheses, which affected the outcome. Clarifications were sought regarding the variables in the formula and the values plugged in. The discussion highlights the importance of proper formula application in solving collision problems.
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Object 1 has a mass of 9.4 kg and is moving eastward with a velocity of 15.3 m/s. It collides with a stationary object. After the collision object 1 recoils with a velocity of -5.3 m/s What is the mass (in kg) of object 2?

m2=35.9kg?

I don't have time to type my work right now. But will show work if answer is wrong to see where i went wrong.
 
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It is wrong.

ehild
 
i used the equation v2=(2m1/m1+m2)vo1 - (m1-m2/m1+m2)vo2
 
You missed some parenteses in the formula. It is wrong without them.

Do you know the meaning of the letters in that formula? What numbers did you plug in?

ehild
 
i think i screwed up getting m2 by itself but i had plugged my numbers in as...

-5.3=((2*9.4)/(9.4+m2))*(15.3)-0
 
-5.3 is the velocity of the object 1. You do not know v2.

ehild
 
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