The coefficient of friction between the block and the surface is determines as 0.1.
Apply the principle of conservation of linear momentum;
0.05(400) = v(0.05 + 25)
20 = 25.05v
v = 0.8 m/s
Apply the principle of conservation of energy
P.E - K.E = Ux
μmgx - ¹/₂mv² = ¹/₂kx²
μ(25.05)(9.8)(0.12) - 0.5(25.05)(0.8)² = 0.5(180)(0.12)
29.459μ - 8.016 = 10.8
29.459μ = 2.784
μ = 0.1
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