The average force that acts on the 8000 kg truck during the collision is 12000kgm/s.
Impulse is the change in momentum of the body.
Mass, M = 8000kg
Time, t = 4s
Mass, m = 12000kg
Velocity, V = 2.5m/s
Let the Final velocity be v.
Using conservation of momentum to find out the final velocity of the truck,
MV = (M+m)v
8000×2.5 = (8000+12000)×v
v = 1m/s
Now the Initial momentum is MV = 8000×2.5 = 20000kgm/s
Final Momentum is Mv = 8000×1 = 8000kgm/s
Change in Momentum = 20000 - 8000
Change is Momentum = 12000kgm/s
Change is momentum is equal to the average force that acts on the truck from the Newton law of motion.
Hence, the average force that acts on the 8000 kg truck during the collision is 12000kgm/s.
Learn more about Impulse here, brainly.com/question/16980676
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