The initial momentum of the ball is 15 Kgms-1.
In Physics, the term momentum is the product of mass and velocity. Momentum is a vector quantity. This implies that momentum possess both magnitude and direction.
Hence, we often write; p = mv
Where:
p = momentum
m = mass
v = velocity
The initial momentum therefore is;
p = 1.25 kg × 12 m/s = 15 Kgms-1
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