The first and third choices on the list will attract, because UNlike poles are facing across the gap.
Choice #1: . . . [S]-----[N] . . . [S]-----[N]
Choice #3: . . . [N]-----[S] . . . [N]-----[S]
After the collision, the momentum didn't change, so the total momentum in x and y are the same as the initial.
The x component was calculated by subtracting the initial momentum (total) minus the momentum of the first ball after the collision
In the y component, as at the beginning, the total momentum was 0 in this axis, the sum of both the first and struck ball has to be the same in opposite directions. In other words, both have the same magnitude but in opposite directions

This is for both balls after the collision, but one goes in a positive and the other in a negative direction.
Answer:
120°
Explanation:
Draw a free body diagram. There are three forces acting on the traffic light. Two tension forces acting along the cables, and weight.
The tension forces have an angle θ between them. That means each tension force forms an angle of θ/2 with respect to the vertical. So the y component of each tension force is:
Ty = T cos (θ/2)
Sum of the forces in the y direction:
∑F = ma
Ty + Ty − W = 0
2 Ty = W
Substituting:
2 T cos (θ/2) = W
If W = T, then:
2 W cos (θ/2) = W
2 cos (θ/2) = 1
cos (θ/2) = 1/2
θ/2 = 60°
θ = 120°
Answer:
a) 1.06*10^-5
b) 0.00105 °C^-1
Explanation:
Given that
Length of the cylinder, L = 1.5 m
Radius of the cylinder, r = 0.25 cm
Voltage across the rod, V = 15 V
I• at Temperature T• = 20° C is 18.5 A
I at Temperature T = 90° C is 17.2 A
See attachment for calculations
First one, insulator. Second one, conductor.