neglecting friction what is the total mechanical energy of ball as it moves along the wooden plane?

Question

Inclined wooden plane by 45º with repect to the table top by placing books under the other edge of the plane. the height of the top of the the wooden plane to the table is 23 cm and the height from the table to the floor is 84 cm. The horizontal distance when the ball fall is 60.5. Neglecting friction what is the total mechanical energy of the ball as it moves along the wooden plane? 

Answer 1

It is conserved, since there is no friction, and therefore it is a constant

 

E = mgh.

 

h depends on what reference point you use for zero potential energy.  You can use the maximum height of the inclined plane above the table surface, as long as you are consistent about it.  

 

m = ?

g = 9.8 m/s²

h = 0.23 meters

 

E = mgh = ?