We will use the formula p = mgh p is potential energy. m is mass of object in kg g is acceleration due to gravity (9.8m/s²) h is height of the objects displacement in meters. p = mgh → mgh = p → h = p / mg p is 14000j, m is 40kg and g is 9.8 m/s² h = 14000 / 40 × 9.8 → h = 1400 / 392 → h = 35.7 Therefore , the cannonball was 35.7 meters high .