Question

Suppose two loaded train cars are moving toward one another, the first having a mass of 1.50 \times 10^5\, \mathrm{kg}1.50×10 5 kg and a velocity of (0.11 \, \mathrm{m/s})\, \hat{i}(0.11m/s) i ^ , and the second having a mass of 1.10 \times 10^5\, \mathrm{kg}1.10×10 5 kg and a velocity of (-0.21 \, \mathrm{m/s})\, \hat{i}(−0.21m/s) i ^ . What is their final velocity?

Answer 1

Answer:

0.2358

Explanation:

We need here  apply the law momentum conservation, for objects who collide.

The equation is given by,

$m_1v_1+m_2v_2= (m_1+m_2)v_f$

Our values are giving by,

$m_1=1.5*10^5Kg\\v_2=0.11m/s\\m_2=1.1*10^5Kg\\v_2=-0.21m/s$

We replace in our equation and solve for V_f, then

$(1.5*10^5)(0.11)+(1.1*10^5)(-0.21)=(1.5*10^5+1.1*10^5)v_f$

$-6600=260000v_f$

$v_f=-\frac{6600}{260000}$

$v_f=-0.2538m/s$

Therefore their final velocity is -0.2358m/s (Negative symbol only indicate change in the direction)