Mass of object m1 = 1 Kg,
Velocity, u1 = 10ms-1
Mass of wooden block m2 = 5Kg,
velocity u2 = 0 (since wooden block is rest)
= 1 × 10 + 5 × 0 = 10 Kgms-1
According to law of conservation of momentum
Momentum after impact = Momentum before impact
(m1 + m2)v = 10
Where v = velocity of combined object
(1 + 5) v = 10
v = \(\frac{10}{6}\) = 1.67ms-1.