Answer:
500 m/s
Explanation:
Momentum, p is a product of mass and velocity. From law of conservation of momentum, the initial momentum equals final momentum
[tex]m_1v_1=m_2v_2\\1000*10=20v_2\\v_2=10000/20=500 m/s[/tex]
Here m and v represent mass and velocity respectively and subscripts 1 and 2 represent car and barrier respectively
Therefore, the velocity of barrier will be 500 m/s