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**1. Homework Statement**

Diver enters the water at 7.92 [ms][/-1] and comes to rest 1.6m below the surface.

Calculate the average total upward force acting on the diver which brings his verticle velocity to zero.

From an earlier part of the questions the divers mass is 72kg.

**2. Homework Equations**

Thus far I have solved this by equating the verticle kinetic engery of the diver on entering the water with the work done by the water in decelerating him to a stop.

The answer I get is [average decelerating force]\approx[/1411N]

The model answer however states that the total average upward force is 1411 + 706 = 2117N.

My question is therefore from where do they / should I get the other 706N from?

**3. The Attempt at a Solution**

[tex]\Delta[/\frac{1}{2}m[v][/2]] = decelerating force x 1.6m

Decelerating force = 0.5 x 72 x [7.92][/2] / 1.6 = 1411N