Question

An object of mass 2kg moving with a velocity of 5m/s collides and sticks to a
stationary wooden block of mass 5kg. They both move off together. Calculate
the speed of the combined object.

Answer 1

Answer:

v=1.428m/s

Explanation:

m1u1+m2u2=v(m1+m2)

2×5+5×0=v(5+2)

10=7v

v=10/7

v=1.428m/s

Answer 2

The speed of the combined object is V = 1.428 m/s.

- Given:

Mass of object, m1 = 2kg

Velocity of object before collision, u1 = 5 m/s

Mass of wooden block, m2 = 5 kg

Velocity of wooden block before collision, u2 = 0 (at rest)

- According to the law of conservation of momentum :

Total momentum before the collision = Total momentum after the collision

m1u1 + m2u2 = (m1 + m2) x V

2 x 5 + 5 x 0 = (2 + 5) x V

V = 10 / 7 = 1.428 m/s