Final answer:
To find the y-component of the net momentum, identify a closed system, calculate the y-components of the individual particles' momentum, and add them together.
Step-by-step explanation:
To find the y-component of the net momentum of the particles, we need to first identify a closed system consisting of particles a and c.
Then, we can write down an expression representing the total momentum of the system before the event.
Next, we calculate the y-components of the momentum vectors for particles a and c using the equation for conservation of momentum in the y-direction. We add these components together to find the final y-component of the net momentum.
Finally, we express the answer in kilogram meters per second as required.