Question #40306

1 Answer
Nov 16, 2016

The mass of the man =76kg=76kg
The downward gravitational force on him
=76xxgN=76xx9.8N=744.8N=76×gN=76×9.8N=744.8N

The mass of the Parachute =5.5kg=5.5kg
The downward gravitational force on it
=5.5xxgN=5.5xx9.8N=53.9N=5.5×gN=5.5×9.8N=53.9N

So total downward gravitational pull
F_gdarr = (744.8+ 53.9)N = 798.7NFg=(744.8+53.9)N=798.7N

The net downward acceleration on the system is 2.6ms^-22.6ms2

So the net downward force

F_ndarr=(76+5.5)xx2.6=211.9NFn=(76+5.5)×2.6=211.9N

Now

F_ndarr=F_gdarr-F_"air"uarrFn=FgFair

=>F_"air"uarr=F_gdarr-F_ndarrFair=FgFn

=>F_"air"uarr=798.7-211.9=586.8NFair=798.7211.9=586.8N

(a) The upward force exerted on the open parachute by the air=F_"air"uarr=586.8N=Fair=586.8N

(b) The downward force exerted by the person on the parachute =744.8N=744.8N