Q6 of 11 Page 83

Calculate the potential energy of a stone of mass 40 kg on the terrace of a building of height 12 m.

Information from the question:-

Mass of the stone = 40 kg


Distance between the ground and the stone = 12 m


Gravitational acceleration = g = 9.8 m/s2


Potential energy- The energy possessed by any object due to its height from the ground or the distance between the object and the ground is called potential energy.


Potential energy = Mass of the object × gravitational acceleration


× distance between the ground and the object


that is , Potential energy = m × g × h


Potential energy = 40 × 9.8 × 12


= 4704 kg m2/s2


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