A block of mass M rests on a block of mass M1 = 5.00 kg

which is on a tabletop. A light string passes over
a frictionless peg and connects the blocks. The coefficient of
kinetic friction mk at both surfaces equals 0.330. A force of
60.0 N pulls the upper block to the left and the lower block to
the right. The blocks are moving at a constant speed. Determine
the mass of the upper block.

I'm trying to combine the equations
f(k) = mu(k) * F(N)
and
F(N) = ( M(1) + M ) * mu * g
to solve for M, but I keep getting really large numbers. :/

2 answers

3.73
Jake how did you get that answer?