In a two-person bobsled race, the first few seconds of the run are crucial. During a practise run on a flat ice surface,where the coefficient...

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The sled is being
pushed by two people, one exerts a force of 503 N and the other exerts a force of 496 N. The
total force exerted is 503 + 496 = 999 N.

If the mass of the sled is
M, we can calculate the force of kinetic friction using the given coefficient of kinetic friction
as M*8*10^-3.

The net force applied on the sled is 999 -
M*8*10^-3

We see that the sled is accelerated at 4 m/s^2 due to the
net force.

So 999 - M*8*10^-3 =
M*4

=> 999 = M(4 +
8*10^-3)

=> M =
999/4.008

=> M = 249.25
kg

The required mass of the sled is 249.25
kg