A 4.00 kg ball traveling North with a momentum of 11.2 kg.m/s collides with a 6.0 kg ball traveling
West with a momentum of 18 kg.m/s. The two balls stick together and head off as one. What is the
momentum of the combined masses? What is the velocity of the combined masses?

Question

A 4.00 kg ball traveling North with a momentum of 11.2 kg.m/s collides with a 6.0 kg ball traveling
West with a momentum of 18 kg.m/s. The two balls stick together and head off as one. What is the
momentum of the combined masses? What is the velocity of the combined masses?

anonymous · Answer

Hi Welcome to Openstudy!

You can also post this in the Physics section :)
Apply the law of momentum: "total initial momentum is equal to the final total momentum of a system".

Since the object A is travelling North and object B is going West, get the resultant vector (the total initial momentum) using their initial momenta that were given. 
|dw:1429501001554:dw|

Then after you calculate the  total initial momentum, apply the law to solve for their velocity:

total initial momentum = total final momentum
total initial momentum = (mass of A + mass of B) * velocity --> since the stuck together after the collision.

From the velocity that you found, calculate the final momentum by:
 (mass of A + mass of B) * velocity calculated

Follow all these steps and you'll be good ^_^