What is the Magnitude of Acceleration in a Frictionless Equation?

AI Thread Summary
To calculate the magnitude of the girl's acceleration while pulling the boy on a frictionless surface, the correct approach involves using Newton's second law, F=ma. The girl exerts a force of 4.50N on the boy, but the acceleration must be calculated using her mass, which is 30.3kg. The confusion arose from initially using the boy's mass instead of the girl's. After correcting this mistake, the proper calculation yields the girl's acceleration. Understanding the application of F=ma is crucial in solving such physics problems.
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Homework Statement


A 30.3kg girl and a 56.0kg boy are on the surface of a frozen lake, 15.0m apart. Using a rope, the girl exerts a horizontal 4.50N force on the boy, pulling him toward her. Calculate the magnitude of the girl's acceleration.

so for this problem i am just confused about the equation to use. i know that it will use a frictionless equation but that is about all that i am sure of.
 
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oh, and i had tried F=ma but that was wrong
 
OK. So, you tried F=ma. That is the equation you should use. I'll need to see your work to help you find your mistake.
 
i figured it out, i was using the guys m and that was the problem
 
OK cool! Good job.
 
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