physics
posted by Chris on .
An elevator with a wieght of 27.8 kN is given an upward acceleration of 1.22 m/s^2 by a cable. a) what is the tension in the cable. b) what is the tension when the elevator is declerating at the rate of 1.22m/s^2 but is still moving upwards?
what exactly is a kN? to find the tension of part a what equation would I use? for b) I need to make a=1.22m/s^2 but I am not sure what the equation I would use be.I should be getting 31.3 kN for a) and 24.3kN for part b but I can't figure out my problem.
Tension= mg + ma when going up.
Tension = mg  ma when going down. Think that out.
kN is kiloNewtons

27.8*9.81+27.8*1.22=306.634