1. The problem statement, all variables and given/known data A medical helicopter weighs 7000 lbs. How much upward force must the propeller supply for it to lift off at 10ft/sec(squared)? 2. Relevant equations T-w=ma, w=mg 3. The attempt at a solution Here is what I tried: T-w=ma.....................w=mg---7000=m(32.2)=217.39k T-7000= 217.39(-10ft/s) T=4826.1 What am I doing wrong here? Shouldnt the acceleration be a negative value since it is going upward? and what should the actual final answer be?