Answer:

Explanation:
Un electrón tiene una carga negativa de
y la masa total es igual al producto del número de electrones y esa carga unitaria. El número de electrones se obtiene al dividir la carga total por la carga unitaria. (An electron has a negative charge of
and the total mass is equal to the product of the qunatity of electrons and such unit charge. The quantity of electrons is found by diving the total charge by the unit charge):



Decision is less important than taking in part of discussions.
When the child is moving, he/she has kinetic energy. For just a brief second before they move the other way, the child is not moving, but they have gravitational potential energy.
The child may need a push from time to time because friction with the air causes loss of energy.
Answer:
v = 15 [m/s]
Explanation:
To solve this problem we must use the principle of conservation of linear momentum, which tells us that momentum is equal to the product of mass by Velocity.

where:
P = linear momentum [kg*m/s]
m = mass = 2 [kg]
v = velocity = 15 [m/s]
![P=2*15\\P=30 [kg*m/s]](https://tex.z-dn.net/?f=P%3D2%2A15%5C%5CP%3D30%20%5Bkg%2Am%2Fs%5D)
Since we know that momentum is conserved, that is, all momentum is transferred to the second body, we can determine the velocity of the second body, since the mass is equal to that of the first body.
![30=2*v\\v = 30/2\\v = 15 [m/s]](https://tex.z-dn.net/?f=30%3D2%2Av%5C%5Cv%20%3D%2030%2F2%5C%5Cv%20%3D%2015%20%5Bm%2Fs%5D)
Answer:
They hold it tightly to their shoulder because the gun recoils and jumps back so by holding it to their shoulder it allows them to stablize the gun so that when it jumps in stead of the gun kicking back and flying the gun jumps and hit the shoulder.
Explanation: