hi, i think it help u,
In the first instance , let’s take it that the wire is a straight line sloping downwards . The problem here is that the equation of the line is not known . If it were known then considering equiangular triangles then the heights of P and R can be calculated . Anyway
The total energy apt P equals that at R
At P , PE + KE = PE +KE at R
At P ; mgh[1] + [1/2]mv[1]^2 = mgh[2] + [1/2]mv[2]^2 at R
2gh[1] + v[1]^2 = 2mgh[2] + v[2]^2
v[2]^2 = 2g ( h[1] -h[2]) +25
v[2] = sq rt [ 20 ( h1 - h2 ) +25]
___________
In a second instance the wire could be circular with a radius r
Measure the angles from the vertical diameter.
Let P subtend an angle x with the centre and diameter
Let R subtend an angle y with the centre and diamerer. This should be easy to draw.
The height of P above the origin is h[1] = r cos x
The height 0f R above the origin is h[2] =r cos y
Again energy is conserved at P and R
At P ; [1/2]mv[1]^2 + mgh[1] = [1/2]mv[2]^2 + mgh[2] , cancel m and multiply by 2
v[1]^2 + 2gh[1] = v[2]^2 + 2gh[2] . Given v[1] , h[1] and h[2] above , then
v[2]^2 = 2g( r cos x - r cos y + 25
v = sq rt [ 20r( cos x - cos y) +25]
Again the radius [ equation of the circle) and the actual positions of P and R are not known to give a particular answer.
The wire could take on many other shapes ; isochrone , etc.
Hope this helps you.