Answer:

Explanation:
<u>Conservation of Momentum
</u>
The total momentum of a system of two particles is

Where m1,m2,v1, and v2 are the respective masses and velocities of the particles at a given time. Then, the two particles collide and change their velocities to v1' and v2'. The final momentum is now

The momentum is conserved if no external forces are acting on the system, thus

Let's put some numbers in the problem and say



120=120
It means that when the particles collide, the first mass returns at 6 m/s and the second continues in the same direction at 28 m/s
Renewable resources are going to be important in our future because if we use up all of our NON-renewable resources now, then we’ll still have the renewable resources to depend on.
I hope this helped! :-)
Answer:
The force is Inertia
Explanation:
The force that acts on an object to move it from rest or a constant straight line motion is known as Inertia.
In physics the above statement is governed by Newton's first law of motion which is also known as Law of Inertia.
This law states that, an object that is at rest will remain at rest and an object that is moving will continue to move in a straight line with constant speed, if and only if the net force acting on the object is zero.
This implies that, A stationary object will remain motionless if no force acts on it while a object with constant velocity will continue moving with constant velocity until a force acts on it (neglecting resistance from air and friction).
According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.