So i was given this question whereby there was an object on a plane inclined at 30 degrees to the horizontal going up the plane being pulled by a string attached to it which is also attached to another object held in the air from a smooth fixed pulley(creating a system). when using work-energy relation what my book has done is :
work done by net force = change in TME
ie W.D by driving force - W.D against resistance = change in TME
ie (0- W.D against resistance) = change in TME
my question is why is the tension not considered as the driving force here?