How to Calculate the Mass of the Second Skater in a Skating Duo?

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To calculate the mass of the second skater, apply Newton's third law, which states that the forces exerted by both skaters are equal in magnitude but opposite in direction. The first skater, weighing 62 kg, accelerates backward at 1.8 m/s², resulting in a force of -18.6 N. By setting the forces equal, you can express the second skater's mass in terms of its acceleration of 2.1 m/s². The equation simplifies to F1 = F2, allowing for the determination of the second skater's mass as the only unknown. This approach effectively utilizes the principles of force and acceleration to solve the problem.
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Homework Statement



A 62-kg ice skater pushes off his partner and accelerates backwards at 1.8m/s2. If the partner accelerates in the opposite direction at 2.1m/s2, what is the mass of the other skater? Assume that frictional forces are negligible.

Homework Equations


F=ma

The Attempt at a Solution


Okay so I found the force the 62kg ice skater exerted. I subtracted the two accelerations and arrived at a -0.3 m/s^2 acceleration from the 62kg ice skater. So I plugged in:

F = (62kg)(-0.3m/s^2)
So the force exerted by the 62kg person is -18.6N. I don't really know where to go from there? I played around with the equation a bit but I can't seem to get anything remotely close to figuring the mass out of the second skater.

Like I'll put the equation as F+18.6N = (m)(0.3m/s^2) But then I'll have two unknowns but not two equations so it just doesn't work out.
 
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In this case, the same quantity of force applies to both guys. In different direction, tough. This works like Pascal's principle, or the sum of kinetic and potential energy of an object.
So, right here, only considering the quantities of force, F1=F2. You can break force into mass and acceleration both as scalar magnitudes. Try it from here.
 
Since both skaters are at rest before they push each other, the net force equals 0.

net F=ma.

You can set the forces equal to each other in terms of mass and acceleration and you should only have one unknown, the mass of the second skater.
 
Thank you Howie!
 
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