-- The gravitational force on Phil is (90kg) x (9.8 m/s²) = 882 Newtons DOWN.
-- The force of air resistance on Phil is 200N UP.
-- If these are the only forces acting on Phil, then the NET force on him is
(882 N down) + (200 N up) = 682 N down .
Newton revealed that F = m a . From this, we also know that a = F / m .
Acceleration = (682 N down) / (90 kg)
Acceleration = (682 / 90) (N/kg) down
Acceleration = 7.58 m/s² down