Answer with Explanation:
Let mass of one vehicle =m
Mass of other vehicle=m'
[tex]\frac{m}{m'}=\frac{1}{4}[/tex]
[tex]m'=4m[/tex]
Velocity of one vehicle=[tex]v=13 im/s[/tex]
Velocity of other vehicle=[tex]v'=13jm/s[/tex]
In x- direction
By law of conservation of momentum
[tex]mv+0=(m+m')V_x[/tex]
[tex]13m=(m+4m)V_x[/tex]
[tex]13m=5mV_x[/tex]
[tex]V_x=\frac{13}{5}[/tex]
In y- direction
By law of conservation of momentum
[tex]0+m'v'=(m+m')V_y[/tex]
[tex]4m(13)=5mV_y[/tex]
[tex]V_y=\frac{52m}{5m}=\frac{52}{5}[/tex]
Magnitude of velocity of the wreck,V=[tex]\sqrt{V^2_x+V^2_y}=\sqrt{(\frac{13}{5})^2+(\frac{52}{5})^2}=10.72 m/s[/tex]
Direction:[tex]\theta=tan^{-1}(\frac{V_y}{V_x})[/tex]
[tex]\theta=tan^{-1}(\frac{\frac{52}{5}}{\frac{13}{5}})=75.96^{\circ}[/tex]