What is the minimum work needed to push a 950-kg car 310 m up a 9.0oincline? a) ignore friction, b) assume the effective coefficient of friction is 0.25 a) Fnet=mg sin =(950 kg) (9.8 m/s2)(sin 9°)= 1456 N W=Fd W=(1456 N)(310 m)= 451,360 J b) Fnet=mg sin - µ mg cos Fnet=(950 kg) (9.8 m/s2)(sin 9°)- (0.25)(950 kg) (9.8 m/s2)(cos 9°)= Fnet=1456 N-2299 N=-843 N W=Fd W=(-843 N)(310 m)= -261330 J Should this be negative? In a rope climb, a 70-kg athlete climbs a vertical distance of 5.0 m in 9.0 s. What minimum power output was used to accomplish this? New to power problems? How should I set this up?