Do Different Weights Fall at the Same Speed When Dropped?

[nukeman]

Homework Statement

OK you have 2 objects. Let's say a wood ball, and a metal ball. Both weigh different weights.

Now, both balls are the exact same surface size.

Both balls are dropped from the exact same height, let's say 5 metres

Now, gravity will not have an effect on them based on their speed correct? (example the heavier ball will not drop faster)

Only when terminal velocity is met by either of them, will the weight of the objects then be different.

Is that correct?

Homework Equations

The Attempt at a Solution

 

[nukeman]

Anyone? :)

 

[Doc Al]

Now, gravity will not have an effect on them based on their speed correct? (example the heavier ball will not drop faster)

Only when terminal velocity is met by either of them, will the weight of the objects then be different.

Is that correct?

These statements are a bit confusing. Their weights are different--you said that up front.

If you dropped them in a vacuum--no air resistance--then they both would have the same acceleration as they fell.

However, given air resistance, they will not have the same acceleration.

If they were to reach terminal velocity, then their accelerations would be zero.

 

[nukeman]

These statements are a bit confusing. Their weights are different--you said that up front.

If you dropped them in a vacuum--no air resistance--then they both would have the same acceleration as they fell.

However, given air resistance, they will not have the same acceleration.

If they were to reach terminal velocity, then their accelerations would be zero.

I always thought that when you drop 2 objects, they will fall at the same speed?

 

[CompuChip]

Now, gravity will not have an effect on them based on their speed correct? (example the heavier ball will not drop faster)

Only when terminal velocity is met by either of them, will the weight of the objects then be different.

I think you are getting things backward.

The very reason they are getting a speed (when dropped from rest) is because gravity has an effect. There is acceleration due to gravity, to be more precise.
What you meant is, that this acceleration is the same for all objects and therefore they will always have same velocity.

You also speak about a terminal velocity, but in theory, the velocity will always keep on increasing. The reason that this does not happen in practice, is because there is usually inconvenient stuff like air around, which exerts a frictional force in the opposite direction. Since, unlike gravitational force, friction does not depend on the mass of the objects, it will be different and they will get different speeds (a.k.a. "heavy things fall faster"). In fact this is the reason of the objects having a terminal - i.e. maximal - velocity, not an effect of it.

 

[Doc Al]

I always thought that when you drop 2 objects, they will fall at the same speed?

Ignoring air resistance, they will. They have the same acceleration due to gravity, and thus will have the same increase in speed as they fall.