The key to solve this problem is the conservation of momentum. The momentum of an object is defined as the product between the mass and the velocity, and it's usually labelled with the letter
:

The total momentum is the sum of the momentums. The initial situation is the following:

(it's not written explicitly, but I assume that the 5-kg object is still at the beginning).
So, at the beginning, the total momentum is

At the end, we have

(the mass obviously don't change, the new velocity of the 15-kg object is 1, and the velocity of the 5-kg object is unkown)
After the impact, the total momentum is

Since the momentum is preserved, the initial and final momentum must be the same. Set an equation between the initial and final momentum and solve it for
, and you'll have the final velocity of the 5-kg object.
The ozone layer is beneficial because it protects us from the ultraviolet (UV) rays from the sun. Without it, survival would be difficult. It is harmful by containing all the pollution and chemicals . That damages our lungs and causes chest pain, coughing,etc.
<span>Answer:
No, because Einstein demonstrated that nothing can exceed the speed of light in a vacuum and for something to happen instantly over that distance would require that speed to be exceeded. If somehow the sun were to vanish, without explosive effects, an enormous gravity wave would begin travelling outward affecting the planets at the speed of light - thus taking about 8 minutes to reach earth.
But that is irrelevant because the only way to remove all that matter would be total conversion of the mass to energy and that energy would totally destroy everything - after the same 8 minutes.
Mike1942f · 9 years ago</span>
Answer:
True
Explanation:
When an object is held higher, it has more potential energy because more energy is stored from its higher position to swing further than it would have, had it been held lower.