A 20 kg objects falls from a height of 30 meters.How many joules of kinetic energy will the object have just before it hits the ground?

The kinetic energy just before hitting the ground can be calculated using the formula KE = 0.5 * mass * velocity^2. Since the object is falling due to gravity, the velocity just before hitting the ground can be calculated using the formula v = √(2 * g * h), where g is the acceleration due to gravity (9.8 m/s^2) and h is the height (30 m). After calculating the velocity, you can use the kinetic energy formula to find the answer.