Question

a force of 8.0N acts on a 2.0kg mass for 5.0s

a. what is the change in momentum of the mass?
b. What is the change in the velocity of the mass?

Answer 1

Lets say its first velocity is 0 m/s .
F=ma 8=2.a a=4m/s^2
after 5s its velocity becomes 0+5.4=20 m/s

a.momentum=mv at the beginnig m.0=0
at the end mv=2.20=40
40-0=40 kgm/s

b. first velocity is 0 final velocity is 20 change is 20-0=20 m/s

Answer 2

how can we assume its initial is 0?

Answer 3

the question ask the change you can assume any value for initial velocity it doesnt change the answer since it asks the change you can check

Answer 4

if you don't mind, go through the math with me step by step with 1 and prove that that leads to the exact same answer .

Answer 5

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