Speed Ratio of Two Children with Different Masses

AI Thread Summary
The discussion revolves around calculating the speed ratio of two children with different masses (45kg and 65kg) after they push off each other. Participants suggest using the principle of conservation of momentum to determine the speed ratio. The initial uncertainty about the problem indicates that additional information may be necessary for a definitive answer. Some participants believe that the answer cannot be determined with the given information. Ultimately, the consensus leans towards needing more context to accurately calculate the speed ratio.
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Two children are facing each other. Child one has mass of 45kg and the other 65 kg. They push off one another and move in opposite directions. What is the ratio of child one's speed to child 2's?
Answer choices:
a 45:65
b 45:110
c 1:1
d 65:45
e can't tell from this info

I don't know where to start, so I'm thinking the answer is e.
 
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solars said:
Two children are facing each other. Child one has mass of 45kg and the other 65 kg. They push off one another and move in opposite directions. What is the ratio of child one's speed to child 2's?
Answer choices:
a 45:65
b 45:110
c 1:1
d 65:45
e can't tell from this info

I don't know where to start, so I'm thinking the answer is e.
Consider conservation of momentum.
 
Surely part of the question has been left off. The children are on skates, so that they move frictionlessly? If so, as Hootenanny said, use conservation of momentum.
 
thanks :)
 
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