1.)Let us assume that the blocks are in motion, and the x-components of their momenta at a certain moment are [tex]p_1[/tex] and [tex]p_2[/tex], respectively. (there's a pic attached)(adsbygoogle = window.adsbygoogle || []).push({});

Find the x-component of the velocity of the center of mass at that moment.

Express your answer in terms of [tex]m_1,m_2,p_1, p_2[/tex]

my answer is [tex]v_{cm} = \frac{m_1*p_1+m_2*p_2}{m_1+m_2}[/tex] but it's incorrect and i dont understand why.

i think p stands for point particle.

also, i have one more quick quesiton:

2.)Suppose that [tex]v_{cm} = 0 [/tex]. Therefore, the following must be true

A.) [tex]p_1 = p_2[/tex]

B.) [tex] v_1 = v_2[/tex]

c.) m1 = m2

d.) none of the above

for this one, i think that if it's equal to zero, both masses should be equal, is this correct?

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# Homework Help: Momentum combination

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