On an unknown planet an object with mass m falls with a speed v₁ at t₁ . At t₂ the object has a kinetic energy KE 2 . Use only energy based calculations to solve the following: m=0.40 kg v₁ =6.0 m/s t₁ =1.0 s t₂ =2.8 s KE₂ =112 J If the object falls a vertical distance 62.38 m between t₁ and t₂ , find the average net force that acted on it.