1. The problem statement, all variables and given/known data Which of the following could be accomplished with the least average force? a: accelerating a 2 kg ball from 0 m/s to 9 m/s in half a second. b: accelerating a 6 kg ball from 0 m/s to 6 m/s in one second. c: accelerating a 9 kg ball from 0 m/s to 8 m/s in two seconds. d: accelerating a 10 kg ball from 0 m/s to 7m/s in two seconds 2. Relevant equations F=ma ma Δt= Δp p=mv 3. The attempt at a solutionAnswer given as correct is D. I used proportions to solve this problem since Δp is proportional to average force. Since initial p is zero for all the problems than Δp is lowest with answer A; pf- pi= 18 kg m/s. If it had asked for force alone than the seconds matter and then you solve for force gives f= Δp/ Δt. If you do it this way a,b, and c all give 36N while d give 35N. But the question does not ask for lowest force it ask for lowest average force. Am I right or did I make a mistake somewhere?