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Guest ProfF

Do heavier objects fall faster than lighter objects?

Do heavier objects fall faster than lighter objects?  

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  1. 1. Do heavier objects fall faster than lighter objects?



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Guest ProfF

Answer the poll, then defend your answer in one well-reasoned paragraph. Respond constructively to another's defense.

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It seems to me that when air resistance comes into play for falling objects, the shape of the object will play an important factor. An object (such as a coffee filter) with lots of surface area in opposition to the air below it will have a different resistance force on it than a straight pencil falling in the same surroundings.

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Guest Elliott56

while it is true that the surface area does seem to affect the speed at which objects fall, it seems that if this surface area and shape are held constant, as they were in the lab, the mass is isolated as the only variable, we can see that as mass increases, ceteris paribus(gotta love AP Econ), the speed at which the object falls also increases

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Guest Keri

I believe that heavier objects do fall faster than lighter objects. In the lab we did in class, there was a significant difference between the speed at which 5 coffee filters fell compared to 1 coffee filter. The mass is very small of a coffee filter, yet resulted in data that still can accurately support the answer 'yes.' The graph of velocity squared compared to time yielded more accurate data than velocity vs time. The velocity squared vs time graph more clearly showed the increase of velocity as time increased, with a line closer to linear than the velocity vs time graph. I see what willorn is saying about the surface area, however I agree with elliott56 in that that does not play much of a role in answering the question do heavier objects fall faster than lighter objects. No matter the surface area, the results should indicate that heavier objects do indeed fall faster than lighter objects.

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Idealy, all objects fall at the same rate. If there were no air resistance, like in a regents physics world, calculated the speed of a falling object is quite easy. However, we do have air resistance and that causes objects to fall at different speeds. In a recent lab that my class did, we used a tracking device and coffee filters, and measured the displacement over time of the coffee filter as it fell to the floor. Suprising, the graphs were always linear, but had a different slope based on the number of coffee filters. This means that the coffee filters, due to the large drag force on them, reached terminal velocity very quickly. The more coffee filters we dropped together (representing higher weights) the steeper the slope. The slope of a Displacement x Time graph is Velocity. Because the slope increased as we added more coffee filters, we can concur that the Terminal velocity increased as we added mass, and heavier objects do fall faster. However, that was for uniform aerodynamics. If we had thrown an array of objects into play, we would have had mixed data. The lightest thing in the world will fall the fastest if it is perfectly aeordynamic.

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No matter the surface area, the results should indicate that heavier objects do indeed fall faster than lighter objects.

I'd like to disagree with this. If you drop a peice of paper (flat side down), and at the same time drop a peice of paper that is crumbled up, the crumbled peice of paper will drop atleast twice as fast. This is because the drag force acts less on the object since it has a lot smaller surface area. Even though they had the same mass, they didnt have the same speed. When you bring this into play, you can see how some lighter objects would fall faster then heavier objects. If you took two peices of paper (doubling the mass by taping two together), and then dropped a crumbled up peice of one paper and dropped both of them simaltaneously, the crumbled up peice of paper would still fall faster because the drag force is smaller. When you look at it this way, it really depends what the shape of the object is. But like Elliot56 put it so well, Ceteris Paribus, as mass increases the terminal velocity increases

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Guest awalts

In the lab that we conducted with the coffee filters, it was evident by the velcoity squared vs. time graph that the more coffee filters he had (and thus the more mass we had), that heavier objects fall faster than ligher objects. The slope of this graph clearly shows that as mass increased, the higher the terminal velocity that was reached. At this point, you're probably wondering why I responded in the poll "it depends" right? The reason that I feel that this relationship is case dependent is because when we tested the coffee filters, we were using ONLY coffee filters, and all the filters were orientarted the same throughout their flight. If you were to drop a piece of paper with the flat side paralle to the ground, it's going to take a long time to drop, and have a low terminal velocity. If you drop that same piece of paper, but instead have the flat side perpindicular to the ground (in other words, the edge faces the ground) its going to fall in a much less amount of time and with a much higher terminal velocity than before, and yet have the same mass. For this question of "do heavier objects fall faster than lighter objects", it really does depend on the aerodynamics of the objects used, as Zac has already stated. Our results point to a "false true" in answer to the question posed, since there was no variety in the aerodynamics of the tested objects.

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Guest caffeinateddd

Using the formula mg=-c(Vt)^2, if we increase the weight mg, Vt must also rise/ Heavier objects fall faster than lighter objects.

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Guest probablykevin

I selected it depends on the poll, but I think there is something else to consider here. First of all, just looking at the data in the lab, adding more coffee filters together resulted in a higher terminal velocity. But what are we actually doing when we put 2 coffee filters together? Do they all of the sudden become one object? Blake's statement of the formula mg=-c(Vt)^2 does indeed support a larger mass increasing the magnitude of terminal velocity. But placing 2 coffee filters on top of each other can be viewed (imo) in 2 ways. First, the mass of the "object" is being doubled and the c value is almost being held constant. Second, the bottom coffee filter is not modified in mass or c value, and the top coffee filter's c value is lowered significantly, causing it to accelerate more quickly into the bottom filter (c and Vt have an inverse relationship).

Overall, changing an object's mass without affecting it's c value is much more complicated than stacking two coffee filters, but when increasing mass ceteris peribus (thanks Elliot), Vt does increase.

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Guest probablykevin

This is because of the c value in mg=-cVt^2

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Guest probablykevin

It seems to me that when air resistance comes into play for falling objects, the shape of the object will play an important factor. An object (such as a coffee filter) with lots of surface area in opposition to the air below it will have a different resistance force on it than a straight pencil falling in the same surroundings.

This is because of c in mg=-c(Vt)^2

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Guest probablykevin

In the lab that we conducted with the coffee filters, it was evident by the velcoity squared vs. time graph that the more coffee filters he had (and thus the more mass we had), that heavier objects fall faster than ligher objects. The slope of this graph clearly shows that as mass increased, the higher the terminal velocity that was reached. At this point, you're probably wondering why I responded in the poll "it depends" right? The reason that I feel that this relationship is case dependent is because when we tested the coffee filters, we were using ONLY coffee filters, and all the filters were orientarted the same throughout their flight. If you were to drop a piece of paper with the flat side paralle to the ground, it's going to take a long time to drop, and have a low terminal velocity. If you drop that same piece of paper, but instead have the flat side perpindicular to the ground (in other words, the edge faces the ground) its going to fall in a much less amount of time and with a much higher terminal velocity than before, and yet have the same mass. For this question of "do heavier objects fall faster than lighter objects", it really does depend on the aerodynamics of the objects used, as Zac has already stated. Our results point to a "false true" in answer to the question posed, since there was no variety in the aerodynamics of the tested objects.

I think this hypothesized dependence of surface area can be attributed to the c-value. Does changing the orientation of an object change it's constant?

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Guest Rellseli66

I feel like heavier objects will fall faster, i mean we have grown up our entire lives believing they will, an that's because objects with more weight will have a larger force of gravity on them, and thus as a result their terminal velocity will be larger, because of the effect of air resistance. I think that surface area is related in a diff way, but when we are just concerned on weight being the independent variable, then the lab shows us that as more weight is added the object will in fact fall faster. If there is more force pushing the object down then it will have a larger terminal velocity bc the air resistance slowing it down will take much longer to slow the object down to a constant rate. The lab shows us that heavy objects fall faster, but it is true that shape an surface area do affect the object, but that can be discussed at a later time

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Guest Rellseli66

exactly max, i totally agree with this, because the only variable changed through out the lab was the wight of the object(nice use of economics btw) an that is why we only change one variable, because the object is to determine just that variables effect, and when we changed the weight we saw the one effect as a result, the object fell faster and the terminal velocity increased

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Guest probablykevin

I feel like heavier objects will fall faster, i mean we have grown up our entire lives believing they will, an that's because objects with more weight will have a larger force of gravity on them, and thus as a result their terminal velocity will be larger, because of the effect of air resistance. I think that surface area is related in a diff way, but when we are just concerned on weight being the independent variable, then the lab shows us that as more weight is added the object will in fact fall faster. If there is more force pushing the object down then it will have a larger terminal velocity bc the air resistance slowing it down will take much longer to slow the object down to a constant rate. The lab shows us that heavy objects fall faster, but it is true that shape an surface area do affect the object, but that can be discussed at a later time

Although I agree that heavier (more massive) objects tend to fall faster ceteris peribus, I disagree with the way it is being supported in this post. While a greater force of gravity is exerted the more massive an object is, the acceleration due to gravity on all objects remains constant. I believe that it was the fact that in this lab we changed mass without altering the air resistance coefficient that caused the changes in terminal velocity. What if someone decided to attach two filters together at the rim and drop them? In that scenario both mass and the air resistance coefficient would increase, theoretically resulting in no change in terminal velocity.

Also, the fact that this post wishes to leave surface area and shape aside when these two attributes have direct effects on the air resistance coefficient voids the whole concept of air resistance.

Finally, it must be noted that if any two objects of any shape and mass were falling in a vacuum, their terminal velocities would be equal, implying that gravity does not have a greater effect on more massive objects.

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This is a fantastic question but I don't know if I should base my answer on real world phenomena or from the perspective of a vacuum world. If you are talking about the real world where there is air resistance than Heavier object will fall faster but than again surface area of the object should also be taken into account. If you are talking about the vacuum word, where there is no air, Both object fall on the same time. It is similar to "Feather-Coin experiment" that is conducted in an enclosed area where it lacks air.

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