Question

Two objects each of mass 1.5 kg are moving in the same straight line But in opposite directions. The velocity of each object is 2.5 metre per second before the collision during which stick together. What will be the velocity of the combined object after collision?​

Answer 1

Answer:

Explanation:

Let us see the information already given in the question.

Mass of object 1 before collision = 1.5 kg

Mass of object 2 moving in opposite direction before collision = 1.5 kg

Velocity of object 1 before collision = 2.5 m s-1

Velocity of object 2 moving in opposite direction before collision = -2.5 m s-1

After collision,

Object 1 sticks to object 2

So, the total mass of the combination = m1+m2

= 1.5 + 1.5 = 3 kg

Let us consider that the velocity of the combination becomes v.

Then, according to the law of conservation of momentum,

Total momentum before collision = Total momentum after collision

So, m1v1 + m2v2 = (m1+m2)v

That is, (1.5 * 2.5) + (1.5 * -2.5) = 3 * v

3.75 – 3.75 = 3v

Therefore, v = 0 m/s

Thus the velocity of the objects after sticking is 0 m/s.

Answer 2

Answer:

m1 = m2 = 1.50 kg

v1 = 2.50 m/sec

v2 = - 2.50  m/sec

m1 v1 + m2 v2 = (m1 + m2) v

1.50 * 2.50 - 1.50 * 2.50 = 0                  =>   v = 0

So the combined momentum is zero.  so  v = 0.