EVERYDAY SCIENCE

Detailed explanation-1: -Work done against gravity in lifting an object becomes potential energy of the object-Earth system. The change in gravitational potential energy, PEg, is PEg = mgh, with h being the increase in height and g the acceleration due to gravity.

Detailed explanation-2: -If an object is lifted, work is done against the force of gravity. When work is done energy is transferred to the object and it gains gravitational potential energy.

Detailed explanation-3: -For the gravitational force the formula is P.E. = mgh, where m is the mass in kilograms, g is the acceleration due to gravity (9.8 m / s2 at the surface of the earth) and h is the height in meters. Notice that gravitational potential energy has the same units as kinetic energy, kg m2 / s2.

Detailed explanation-4: -Since the gravitational potential energy of an object is directly proportional to its height above the zero position, a doubling of the height will result in a doubling of the gravitational potential energy. A tripling of the height will result in a tripling of the gravitational potential energy.

Detailed explanation-5: -An object’s gravitational potential is due to its position relative to the surroundings within the Earth-object system. The force applied to the object is an external force, from outside the system. When it does positive work it increases the gravitational potential energy of the system.