Answer:
-[tex]29.2\times 10^{3} N[/tex]
Explanation:
We are given that
Mass of cars= m=1900 kg
Initial speed of car=u=20 m/s
Final speed of car=v=0
Time=[tex]\Delta t[/tex]=1.3 s
We have to find the average force exerted on the car.
Average force=[tex]\frac{change\;in\;momentum}{\Delta t}[/tex]
[tex]F_{avg}=\frac{mv-mu}{1.3}[/tex]
[tex]F_{avg}=\frac{1900(0)-1900(20)}{1.3}[/tex]
[tex]F_{avg}=\frac{-38000}{1.3}=-29.2\times 10^{3} N[/tex]
Hence, the average force exerted on the car that hits a line of water barrels=-[tex]29.2\times 10^{3} N[/tex]