Raising an object increases the gravitational potential energy of the object–Earth system. Calculate the change using ΔEₚ = mgΔh with height in metres. When an object falls, the decrease can increase its kinetic store or be dissipated by resistance. Example: Calculate the gain in gravitational potential energy when 3 kg rises 4 m. Use g = 10 N/kg. ΔEₚ = mgΔh = 3 × 10 × 4 = 120 J. Rearrange the relationship before substituting if a different quantity is required. Explain the result. Use evidence.