Answer:
The kinetic energy of the system after the collision is 9 J.
Explanation:
It is given that,
Mass of object 1, m₁ = 3 kg
Speed of object 1, v₁ = 2 m/s
Mass of object 2, m₂ = 6 kg
Speed of object 2, v₂ = -1 m/s (it is moving in left)
Since, the collision is elastic. The kinetic energy of the system before the collision is equal to the kinetic energy of the system after the collision. Let it is E. So,

E = 9 J
So, the kinetic energy of the system after the collision is 9 J. Hence, this is the required solution.
Answer:
it would take rod B twice as much time
Explanation:
it would take rod B twice as much time as it is twice as thick and twice as long. Due to this reason it would take the electric charge not only more time but even more voltage to travel through the rod
The answer is C,<span> The sum of all forces acting on the object is zero. hope that helps!!</span>