Based on the calculations, it would take 7.5 seconds before the final velocity of this object would be equal to three times its initial velocity.
Given the following data:
Mathematically, acceleration can be calculated by using the first equation of motion:
v = u + at
Where:
Making t the subject of formula, we have:
t = (v - u)/a
Substituting the given parameters into the formula, we have:
t = (45 - 15)/4
t = 30/4
t = 7.5 seconds.
Read more on acceleration here: brainly.com/question/24728358
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