Question

HELPPPPPPP !!!!!! PLS A 0.050 kg Truck moving right at 0.20 m/s collides with a toy race car weighing 0.015 kg initially at rest on a frictionless track. the truck keeps moving right at 0.15 m/s after Collision what is the final speed of the race car?

Answer 1

Answer:

$v_f=0.15\:\mathrm{m/s}$

Explanation:

From the Law of Conservation of Momentum, we can write the following equation:

$m_1v_1+m_2v_2=m_fv_f$

Because the toy car was initially at rest, $m_2v_2=0$.

Therefore, we can plug in given values and solve for $v_f$:

$m_1v_1=m_fv_f,\\0.050\cdot 0.20 = (0.050+0.015)v_f,\\v_f=\fbox{ 0.15\:\mathrm{m/s} }$ (two significant figures).