Newton's First law - Dropping a feather and a hammer....

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<<Mentor note: Edited for language>>

1. Homework Statement
If I have a feather and a hammer and drop it at the same time from the same height (with out air resistance, so basically in a vacuum) Why would it land on the ground at the exact same time?

Homework Equations

F = ma

The Attempt at a Solution

My assumption is that with the equation posted above, which I think has nothing to do with why it drops at the same time, even though they both have different masses but the same acceleration.

- Also, would it accelerate because the only force is gravity (9.8)...but that's a force so would it be -9.8 = m*a ?

<<*edited*>> I'M SO CONFUSED

taking physics in college and I'm already in chapter 9 which is center mass and linear momentum, and just barely understanding force and motion which is chapter 5 while midterm is next tues <<*edited*>>

 

[SammyS]

Homework Statement

If I have a feather and a hammer and drop it at the same time from the same height (with out air resistance, so basically in a vacuum) Why would it land on the ground at the exact same time?

Homework Equations

F = ma

The Attempt at a Solution

My assumption is that with the equation posted above, which I think has nothing to do with why it drops at the same time, even though they both have different masses but the same acceleration.

- Also, would it accelerate because the only force is gravity (9.8)...but that's a force so would it be -9.8 = m*a ?

I'M SO CONFUSED

taking physics in college and I'm already in chapter 9 which is center mass and linear momentum, and just barely understanding force and motion which is chapter 5 while midterm is next tues -.-

You probably need to review some basic concepts. What is meant by each of the following?

acceleration

acceleration due to gravity.

Weight (of an object)

 

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You probably need to review some basic concepts. What is meant by each of the following?

acceleration

acceleration due to gravity.

Weight (of an object)

And you might want to edit your post just a bit to remove what might be considered offensive.

a feather and a hammer or anything heavier will have a different mass compared to the feather. Acceleration is 9.8 but the forces will be different because of different masses, basically i still don't see how they will end up on the ground at the same time due to different forces and different masses

 

[SammyS]

a feather and a hammer or anything heavier will have a different mass compared to the feather. Acceleration is 9.8 but the forces will be different because of different masses, basically i still don't see how they will end up on the ground at the same time due to different forces and different masses

If acceleration is the same, and the initial velocity is the same, then the motion is the same, Right?

 

[copypacer]

If acceleration is the same, and the initial velocity is the same, then the motion is the same, Right?

Right, but I thought the time it would get there would be different because the hammer would have a greater force because of its greater mass.

My guess is that because the hammer has a greater mass, that mass compensates for the greater force and essentially, the ratio of Force to mass is the same as for the feather. The ratio of force to mass which is acceleration is the same for the hammer as for the feather and that is why both of them land at the same time.

 

[SammyS]

Right, but I thought the time it would get there would be different because the hammer would have a greater force because of its greater mass.

My guess is that because the hammer has a greater mass, that mass compensates for the greater force and essentially, the ratio of Force to mass is the same as for the feather. The ratio of force to mass which is acceleration is the same for the hammer as for the feather and that is why both of them land at the same time.

Right. The ratio of force to mass is the same for both.

 

[copypacer]

You probably need to review some basic concepts. What is meant by each of the following?

acceleration

acceleration due to gravity.

Weight (of an object)

When you said "weight" do you mean mass?...but then again this is in respect to gravity right? confused

 

[SammyS]

When you said "weight" do you mean mass?...but then again this is in respect to gravity right? confused

When you said "weight" do you mean mass?...but then again this is in respect to gravity right? confused

No. Look in your textbook or notes for the definition of weight.

Weight is not the same as mass.

 

[toesockshoe]

I have a question... isn't this more of a kinematics problem than a F=ma problem?

 

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No. Look in your textbook or notes for the definition of weight.

Weight is not the same as mass.

I know, weight has to do with gravity, BUT, we still call it mass because we need the measurement of matter in the object and than calculate the gravity in order to find the force.Also, if I wanted to find what my mass is, do I just divide my weight by 9.8?

 

[SammyS]

I know, weight has to do with gravity, BUT, we still call it mass because we need the measurement of matter in the object and than calculate the gravity in order to find the force.Also, if I wanted to find what my mass is, do I just divide my weight by 9.8?

Mass is a measure of an objects inertia.

Gravity is the force exerted on an object due to gravity.

An isolated object that is not in any gravitational field still has mass. The mass of that object is the same no matter how much gravity is present.