Question:
If two objects of different weights are dropped form the
same height, which one will reach the ground first?
Why? What is the scientific explanation and how would I teach it to
children?
Replies:
There is a classic physics experiment in which a feather is placed inside
a sealed tube. The air is then pumped out of the tube. Next, the tube is
turned upside down and the feather falls like a rock.
The acceleration of a falling object in a gravitational field is a
constant. It does not depend on the weight, size, or shape of the
object. What does depend on these factors (at least on the size and
shape) is the drag (or resistance to motion) in the air. In the absence
of air, all objects fall at the same rate. In the presence of air the
object that is most stream-lined (for equal weights) or the heaviest
object (for same shape and size) will hit first.
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