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**Background question:**

A bicycle and rider have a combined mass of 75 kg. They freewheel down a slope whose maximum height is 6 meters above sea level. The slope is 20 meters long. At the end of the slope, the bicycle and rider are travelling with a velocity of 10 m/s. Calculate the work done against friction whilst descending the slope.

**Answer reached:**

mass = 75 kg

max. height = 6 meters

slope = 20 meters

Vf = 10 m/s

PE at start = KE at end + work done to overcome friction.

mgh = 1/2mv

^{2}+ friction force x distance moved against friction.

= 75 x 9.81 x 6 = 1/2 x 75 x 10

^{2}+ f x 20

= 4414.5 = 3750 + 20f

= 4414.5 - 3750 = 20f

= 664.5 = 20f

Force = 664.5/20

Force = 33.225N

**Question needing assistance with:**

Using the calculated values from the question above, calculate how far the bicycle will travel before coming to a stop if the surface of the road is the same as the slope. State why this distance would not be achieved in a real world experiment.