a skater is sliding forward on a flat rink at 6 m/s. her mass is 71 kg. the sliding friction acting on her skate blade is 13.4 N acting backward. air resistance is 14.7 N acting backward. what is her horizontal acceleration?
F=ma
=>
a=F/m
F=-(13.4+14.7) N
m=71 kg
evaluate acceleration (should be negative)