1. The problem statement, all variables and given/known data A mass of 80 kg rests on the floor of a lift. (Take g = 10ms-2). Calculate: (a) the reaction force exerted on the object by the floor, when the lift is travelling at a steady speed of 2 ms-1 downwards. (b) the reactive force exerted on the object by the floor of the lift, as its downward motion is brought to rest by a retardation of 4ms-2. (c) the reactive force exerted on the object by the floor, when the lift is at rest. Gravity = 10 m/s-2 2. Relevant equations F=M.A 3. The attempt at a solution (a) becuase there is a steady speed downwards, do i just use gravity as the accelleration and nothing else? so F= (80) x (10) F=800 N /or/ is it F= (80) x (10+2) F=960 N (b) F= (80) x (10-4) so F= 480 N (c) F= (80) x (10) F=800 My teacher this year has been pretty useless if you could help me understand this i would be really gratful.