Can gravity do work on an object?
1 Answer
Yes
Explanation:
To do work on an object, gravity must have two properties:
It exerts a force on an object.
It is possible for that object to move in the direction of the force of gravity (or any direction non-perpendicular to the force)
To show that both of these statements are true, let's find an example where they are both true.
Let's say I have a basketball and I'm holding it 2 meters above the ground. If I drop it, gravity acts on the ball at a rate of
When I drop it, the ball travels straight downwards for 2 meters before hitting the ground. Since the direction of gravity is "down", the ball has moved in the direction of the force of gravity.
Therefore, gravity has done work on the basketball!
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Bonus:
To find the work done on the basketball, we use this formula:
#"work" = "force" xx "distance"#
#"work" = 9.8 ("kg" * "m")/"s"^2 xx 2 "m"#
#"work" = 19.6 color(white)"." ("kg" * "m"^2)/"s"^2#
So this is the amount of work that gravity did on the basketball.
