Hey there all of you. I am doing some studying for my final for physics and i have come across this question. I thought it was easy but it is not working that way. The question is. A 4kg block (held by a block) is accelerating down at 3 m/s/s, what is the tension of the rope? So I am thinking to do this: Fnet = ma T - Fg = ma T = ma + mg T = 4kg(-3m/s/s) + 4kg(-9.8m/s/s) T = 51N So I look at the answer and it is wrong, it says it is: 27N So now I try making the opposite end negative. Fnet = ma Fg - T = ma - T = ma - mg T = -ma + mg T = -4kg(-3m/s/s) + 4kg(-9.8m/s/s) T = 27N Now I am getting the right answer. However I can not get the correct answer doing the same question the other way, so my question is what am I doing wrong? Thank you.