Answer: 4.41 joules
Step-by-step explanation:
Given that:
work is done by gravity = ?
Mass of pine cone (m) = 50g
Convert mass in grams to kilograms
Since 1000g = 1kg
50g = (50/1000) = 0.05kg
Height of tree (h) = 9 m
Apply the formula for work,
Work = mass x acceleration due to gravity x height
Acceleration due to gravity has a value of 9.8m/s^2
Work = mgh
Work = 0.05kg x 9.8ms^2 x 9m
Work = 4.41J
Thus, 4.41 joules of work is done by gravity.