Kindly have a look at the attached image for the related question.
I've solved (i) to get the following values...
a= 2.5 ms^-2
T= 3.75 N
I want to inquire about part (ii)
What I want to know is that since acceleration of A was 2.5 then the acceleration of B should be -2.5 ... no?
I ask this because, for part (ii) I've got the correct answer of 'mass' by using
But if I use -2.5 then the answer comes out to be m=0.5 kg.
What am I doing wrong?
in body B, if you use acceleration -2.5 , this means you are considering the upwards direction to be negative
so you need to consider T also negative because its upwards and the weight to be positive because its downwards
considering the opposite. downwards negative and upwards positive.
its also works
as long as same direction vectors have the same signal