# The height of a slope making an angle of 30 degrees with the horizontal is 36 m. What is the velocity of an object that slides down from the top. You need to apply the principle of conservation of mechanical energy such that: `mgh = (mv^2)/2 =gt 2gh = v^2 =gt v = +-sqrt(2gh).`

Considering the motion of object frictionless, hence `v = sqrt(2gh).`

The problems provides the value of height, hence the angle made by slope to x axis...

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You need to apply the principle of conservation of mechanical energy such that: `mgh = (mv^2)/2 =gt 2gh = v^2 =gt v = +-sqrt(2gh).`

Considering the motion of object frictionless, hence `v = sqrt(2gh).`

The problems provides the value of height, hence the angle made by slope to x axis is of no need in this problem. You need to know the angle only if the length of slope is known but the height is not given.

Substituting  is`9.8 m/(s^2)`  for g and 36 m for h yields:v = `sqrt(2*9.8*36) ` => `v~~ 26.56 m/s`

Hence, evaluating the velocity of object sliding down from the top of slop yields: v~~ 26.56 m/s.

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