10. In an elastic collision, an object with momentum 25 kg. m/s collides with another object moving to the right that has a

momentum 35 kg . m/s. After the collision, both objects are still moving to the right, but the first object's momentum

changes to 10 kg. m/s. What is the final momentum of the second object?

a. 10kg. m/s

b. 20 kg · m/s

c. 35 kg · m/s

d. 50 kg · m/s

(d) 50 kg · m/s

Explanation:

Given;

initial momentum of first object, m₁u₁ = 25 kg. m/s

initial momentum of second object, m₂u₂ = 35 kg . m/s

final momentum of the first object, m₁v₁ = 10 kg. m/s

final momentum of the second object, m₂v₂ = ?

O > + O> = O> + O>

Apply the principle of conservation of linear momentum;

m₁u₁ + m₂u₂  = m₁v₁ + m₂v₂

25 + 35 = 10 + m₂v₂

60 - 10 = m₂v₂

50 = m₂v₂

Therefore, the final momentum of the second object is 50 kg. m/s

(d) 50 kg · m/s

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be