1. The problem statement, all variables and given/known data A 40kg branch falls 5.5m and lands on a roof. The roof withstood the the impact. 2. Relevant equations If the impact time was 0.4 second calculate the magnitude of the average force exerted on the roof during the impact. 3. The attempt at a solution F=ma doesn't seem right because it's in free fall though. P=mv ≈ 415 415/0.4=1037.5N? Is this right?