The momentum of truck is 20790 kg m/s
Solution:
Given that we have to find the momentum of truck
From given, 1155 kg truck has a velocity of 18 m/s
Therefore,
Mass = 1155 kg
Velocity = 18 m/s
The momentum is given by formula:

Where, m is mass in kg and v is velocity in m/s
Substituting the values we get,

Thus momentum of truck is 20790 kg m/s