A3.0kg mass is held 4.2 m above the ground. what is the potential energy of the mass with respect to the ground?

126 joules

Potential energy is the energy possessed by a body while at rest.

It is calculated by the formula m×g×h; where m is the mass, h is the height and g is the gravitational acceleration, 10N/kg

Potential energy = m×g×h

                           = 3.0 × 4.2 × 10

                           =  126 joules

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