Answer :
The answer is C. 50 s
Given: M = 40 Kg; Vi = 2 m/s; Vf = 12 m/s; F = 8 N
Formula: F = ma but a = Vf - Vi/t substitute acceleration "a" from F = ma
F = m(Vf - Vi)/t Solve for time "t" t = m(Vf - Vi)/F
t = 40 Kg (12 m/s - 2 m/s)/8 Kg.m/s²
t = 50 s
Given: M = 40 Kg; Vi = 2 m/s; Vf = 12 m/s; F = 8 N
Formula: F = ma but a = Vf - Vi/t substitute acceleration "a" from F = ma
F = m(Vf - Vi)/t Solve for time "t" t = m(Vf - Vi)/F
t = 40 Kg (12 m/s - 2 m/s)/8 Kg.m/s²
t = 50 s