An 80 kg person standing on a 20 kg plateform is suspended by a rope passing over a stationary pulley that is free to rotate. The other end of the rope is held by the person. The masses of the rope and pulley are negligible. You may use g=10 m/s/s. Assume that friction is negligible and the parts of the rope shown remain verticle. ok.. so the whole system is 100kg = 1000N right? (a) if the platform and the person are at rest, what is the tension in the rope? T=NetForce-Mg (i think) so mg = 1000N and NF= 1000N too?? The person now pulls on the rope so that the acceleration of the person and the platform is 2m/s/s upward. (b) What is the tension in the rope under these new conditions? would NF change? (c) Under these new conditions, what is the force exerted by the platform on the person? F= ma so... platform on person.... 20kg on 80 kg.. accel is 2... um... confused...what do i do now? After a short time, the person and the platform reach and sustain and upward velocity of 0.4m/s (d) Determine the power output of the person required to sustain the velocity. Hm... he hasn't taught us power yet... A little help please?