answer:
MAXIMUM SPEED
explanation:
IM SURE THAT IS THE ANSWER
If everything else is held constant ... the substance from which
the conductor is formed, its cross-sectional area, its temperature
everywhere along its length ... then yes, its resistance will be
directly proportional to its length.
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.