This is a question I took previously. All my colleagues got [MATH]5 \ m/s[/MATH], but I got [MATH]4 \ m/s[/MATH].
Here how I did it.
initial momentum = final momentum
[MATH]m_1 \ v_{1i} + 0 = m_{B} \ v_{2f} + m_1 \ v_{1f}[/MATH]
where [MATH]m_1[/MATH] is the mass of the bullet, [MATH]m_B[/MATH] is the mass of the block, [MATH]v_{1i}[/MATH] is the initial velocity of the bullet, [MATH]v_{1f}[/MATH] is the final velocity of the bullet, and [MATH]v_{2f}[/MATH] is the final velocity of the block
solving for [MATH]v_{2f}[/MATH]
I got
[MATH]v_{2f} = \frac{m_1 \ v_{1i} - m_1 \ v_{1f}}{m_B} = \frac{0.01(500 - 100)}{1} = 4 \ m/s[/MATH]
Is there anything wrong with my calculations?
