The momentum of the first truck is 40,000 kgm/s.
The velocity of the second truck with equal momentum is 28.57 m/s.
The given parameters:
The momentum of the first truck is calculated as follows;
P = mv
P = 4000 x 10
P = 40,000 kgm/s
The velocity of the second truck with equal momentum is calculated as follows;
[tex]P = mv\\\\v = \frac{P}{m} \\\\v = \frac{40,000}{1,400} \\\\v = 28.57 \ m/s[/tex]
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