A4kg vase sits on a shelf at a height of 1.2m. how much gravitational potential energy is added to the vase when it is lifted to a shelf of height 1.4m?

ΔU=7.84 J  : Potential energy added to the vase

Explanation:

Conceptual analysis

Potential Energy (U) is the energy of a body located at a certain height (h) above the ground and is calculated as follows:

U = m * g * h

U: Potential Energy in Joules (J)

m: mass in kg

g: acceleration due to gravity in m/s²

h: height in m

Equivalences

1 N = 1 (kg×m)/s²

1 J = N × m

Known data

m = 4kg

g=9.8 m/s²

h₁=1,2 m

h₂=1.4m

Problem development

Potential energy added to the vase =ΔU

ΔU: Potential energy change

ΔU = U₂ - U₁

ΔU = m*g*h₂ - m*g*h₁

ΔU = m*g*(h₂ - h₁)

ΔU = 4*9.8*(1.4 – 1.2)

ΔU=39.2*(0.2) ΔU=7.84 J  : Potential energy added to the vase

the displacement produced by the body.  

the amount of force subjected to the body.  

the angle between the direction of force and displacement