How Do You Calculate the Velocity of the Center of Mass?

[akaur]

1. Recall that the blocks can only move along the x axis. The x components of their velocities at a certain moment are v1x and v2x. Find the x component of the velocity of the center of mass (vcm)x at that moment. Express your answer in terms of m1, m2, v1x, and v2x



2. Keep in mind that, in general: v= dx/dt.



3. its the derivative of xcm = (m1x1 + m2x2) / (m1 + m2)...so does vcm= [(m1)(v1x) + (m2)(v2x)] / (m1 + m2) ?

 

[learningphysics]

1. Recall that the blocks can only move along the x axis. The x components of their velocities at a certain moment are v1x and v2x. Find the x component of the velocity of the center of mass (vcm)x at that moment. Express your answer in terms of m1, m2, v1x, and v2x



2. Keep in mind that, in general: v= dx/dt.



3. its the derivative of xcm = (m1x1 + m2x2) / (m1 + m2)...so does vcm= [(m1)(v1x) + (m2)(v2x)] / (m1 + m2) ?

yes. looks right to me.

 

[amalmaru]

what if you don't have the masses, cause I am stuck on one question that has just 2 velocities going in the positive x direction