i know it’s 30 but how ??? what equations did you use and how do you get there ?
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The change in momentum of the object between 0 and 4s is 40 Ns.
The momentum of an object is determined from the product of mass and velocity of the object.
The change in momentum of an object is equal to the impulse received by the object.
ΔP = J = Ft
where;
The change in momentum of the object between 0 and 4s is calculated as follows;
ΔP = Ft
ΔP = 10 x 4
ΔP = 40 Ns
Learn more about change in momentum here: https://brainly.com/question/7538238