Spring with 2 masses rotating and vibrating

[ross0523]

Homework Statement

Consider an object consisting of two balls connected by a spring, whose stiffness is 400N/m.
The object has been thrown through the air
and is rotating and vibrating as it moves. At
a particular instant the spring is stretched
0.3m, and the two balls at the ends of the
spring have the following masses and velocities:

m1= 1.4kg v1= <5.5, -5.5, 0>
m2=3.4 kg v2=<-13.5, 8, 0>

What is x and y components of V(center mass)?
What is K total=?

Homework Equations

Ktot= K trans + K rel
Psys= M(total)V(cm)
U=1/2 kx^2
Ke=1/2 mv^2
Ke= 1/2 I w^2


3. The Attempt at a Solution :

I tried to just solve for center of mass and apply x and y velcoities but it didnt work.

 

[vela]

Homework Statement

Consider an object consisting of two balls connected by a spring, whose stiffness is 400N/m.
The object has been thrown through the air
and is rotating and vibrating as it moves. At
a particular instant the spring is stretched
0.3m, and the two balls at the ends of the
spring have the following masses and velocities:

m1= 1.4kg v1= <5.5, -5.5, 0>
m2=3.4 kg v2=<-13.5, 8, 0>

What is x and y components of V(center mass)?
What is K total=?

Homework Equations

Ktot= K trans + K rel
Psys= M(total)V(cm)
U=1/2 kx^2
Ke=1/2 mv^2
Ke= 1/2 I w^2


3. The Attempt at a Solution :

I tried to just solve for center of mass and apply x and y velcoities but it didnt work.

What is that supposed to mean? Show your work.