Answer:
NO HAY TRABAJO REALIZADO YA QUE EL NIÑO NO PUDO MOVER
EL ARMARIO, PARA QUE HAYA TRABAJO DEBE HABER DESPLAZAMIENTO.
Explanation:
Answer:
Radio astronomy began in 1933 when an engineer named Karl Jansky accidentally discovered that radio waves come not just from inventions we create but also from natural stuff in space.
Answer:
Yes, if the carts are travelling into opposite directions
Explanation:
The total momentum of a two carts system is the sum of the momenta of the individual carts:

where
m1, m2 are the masses of the two carts
v1, v2 are the velocities of the two carts
In order to have a total momentum of zero, we must have
(1)
Let's remind that velocity (and so, momentum as well) is a vector quantity: this means that it has a direction, so when summing together the momenta, we must also consider the sign of the velocity, depending on its direction.
Therefore, if the two carts are moving in opposite directions, the signs of the two velocities will be opposite. For example, we can have

This means that the condition in eq.(1) can be satisfied, provided that the two carts are travelling into opposite directions.