It is past midnight and sue is sliding down a rope from her third floor window to meet her boyfriend. as she slides down the rope faster and faster she becomes alarmed and gradually tightens her grip on the rope. thus the tension in the rope gradually increases. when the tension becomes equal to sue's weight (ignore the mass of the rope),

(a) sue will stop.
(b) sue will slow down.
(c) sue will continue downward at constant speed
(d) the rope will break

When the tension becomes equal to Sue's weight, she will continue downward at constant speed.

Option C

Explanation:

It’s a simple and easy problem on physics. Here the frame of reference is the person Sue herself. She is going down the rope and the tension at a point on the rope is the weight of Sue herself. So at that point the force acting on Sue is her weight which is going downwards.

But it’s cancelled by the equal force that is the tension on the rope. At that particular point there’s no external resultant force that’s acting on Sue. So the speed at which Sue was descending remains constant.  

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.