Do Different Weights Fall at the Same Speed When Dropped?

In summary: However, in the real world, air resistance (or other factors like shape, surface area, etc.) can affect the speed of an object as it falls. This is why heavier objects with more mass may fall faster than lighter objects with less mass, because they are able to push through air resistance more easily. Terminal velocity is the maximum speed an object can reach as it falls, when the force of air resistance equals the force of gravity. At this point, the weight of the objects will not have an effect on their speed.
  • #1
nukeman
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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

 
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  • #2
Anyone? :)
 
  • #3
nukeman said:
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.
 
  • #4
Doc Al said:
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?
 
  • #5
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.
 
  • #6
nukeman said:
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.
 

Related to Do Different Weights Fall at the Same Speed When Dropped?

1. What is acceleration?

Acceleration is the rate of change of an object's velocity over time. It is a vector quantity, meaning it has both magnitude (how much the velocity changes) and direction (the direction in which the velocity changes).

2. How is acceleration calculated?

Acceleration can be calculated by dividing the change in velocity by the change in time. This can be represented by the formula a = (vf - vi) / t, where a is acceleration, vf is final velocity, vi is initial velocity, and t is time.

3. What are the units of acceleration?

The units of acceleration are distance over time squared, or length divided by time squared. In the SI (International System of Units), the unit for acceleration is meters per second squared (m/s^2).

4. How does acceleration relate to force?

According to Newton's second law of motion, an object's acceleration is directly proportional to the net force acting on it and inversely proportional to its mass. In other words, the more force applied to an object, the greater the acceleration, and the more massive the object, the less it will accelerate.

5. What is the difference between acceleration and velocity?

Velocity is the rate of change of an object's position over time, while acceleration is the rate of change of an object's velocity over time. In other words, velocity tells us how fast an object is moving and in what direction, while acceleration tells us how much the velocity is changing and in what direction.

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