Assuming there isn't any friction, this tension force is the net force. It's the only horizontal force. And for that reason we have this formula for it then: mass times acceleration. We'll substitute in the mass of nine hundred sixty kilograms times the acceleration of one point two zero meters per second squared giving an answer of one point one five times ten to the three Newtons required for this rope to withstand, in the 6th Edition. In the 5th Edition the mass is one thousand fifty kilograms giving a 5th Edition answer of one point two six times ten to the three Newtons.