Egg Drop and Newtons! (1 Viewer)

derfee

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I've been wondering for a long time, after applying Newton's second law on an egg drop, is that the force that occurs when it hits the ground?
 

random-1006

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I've been wondering for a long time, after applying Newton's second law on an egg drop, is that the force that occurs when it hits the ground?

when the egg is failling, newton 2nd law is beig demonstrated , ie a mass experiences a gravitational that cause it to accelerate, F=Ma

when the egg hits the ground , newtons third law states that the force the egg exerts on the ground is equal and opposite dirrection to the force that the ground exerts on the egg
 

derfee

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when the egg is failling, newton 2nd law is beig demonstrated , ie a mass experiences a gravitational that cause it to accelerate, F=Ma

when the egg hits the ground , newtons third law states that the force the egg exerts on the ground is equal and opposite dirrection to the force that the ground exerts on the egg
Is there any relation between the F=Ma force and Newton's third law during the drop?
 

random-1006

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Is there any relation between the F=Ma force and Newton's third law during the drop?
no, i remember physics lecturer said something about the newtons third law to a falling ball

Newtons third law applied to the failling ball is :

The gravitational force of the ball exerts a ( attractive) force on the earth , and by newtons second law the earth exerts a ( attractive ) force on the ball.

F= ma : NEWTON 2ND LAW

F( ab) = -F (ba) : NEWTONS 3RD LAW

the so called "action and reaction" are exerted on DIFFERENT objects for NEWTON 3 , thats the key

im pretty sure of this, but not 100%
 
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addikaye03

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Is there any relation between the F=Ma force and Newton's third law during the drop?
Well consider the egg as a point source. The egg experiences a gravitational attraction (a force, +-mg depending upon which direction you define as positive. Basically U=mgz therefore dU/dz=mg) towards the centre of the primary mass (in this case Earth).

So what other forces does the egg experience?
-A resistive force due to air

Now when the egg hits the ground there is a transfer of energy. This collision is inelastic (completely negligable since the mass of Earth is so large, Newton's third Law). Conservation of momentum can be used to show how inelastic collision is negligable. Ptotal=P1+P2. Some energy is lost to heat, deformation etc. Impact force can be calculuted by: J= integration of Force over time.

Here's a basic outline

p.s: obviously, Fnet=ma=mg-air resistance (usually 1/4Av^2) therefore a=g-1/4m*Av^2
 
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derfee

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no, i remember physics lecturer said something about the newtons third law to a falling ball

Newtons third law applied to the failling ball is :

The gravitational force of the ball exerts a ( attractive) force on the earth , and by newtons second law the earth exerts a ( attractive ) force on the ball.

F= ma : NEWTON 2ND LAW

F( ab) = -F (ba) : NEWTONS 3RD LAW

the so called "action and reaction" are exerted on DIFFERENT objects for NEWTON 3 , thats the key

im pretty sure of this, but not 100%
Oh, I was getting really confused because when ball was being dropped at different heights they had the same amount of force on them.
Thanks for your help!
 

derfee

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Well consider the egg as a point source. The egg experiences a gravitational attraction (a force, +-mg depending upon which direction you define as positive. Basically U=mgz therefore dU/dz=mg) towards the centre of the primary mass (in this case Earth).

So what other forces does the egg experience?
-A resistive force due to air

Now when the egg hits the ground there is a transfer of energy. This collision is inelastic (completely negligable since the mass of Earth is so large, Newton's third Law). Conservation of momentum can be used to show how inelastic collision is negligable. Ptotal=P1+P2. Some energy is lost to heat, deformation etc. Impact force can be calculuted by: J= integration of Force over time.

Here's a basic outline

p.s: obviously, Fnet=ma=mg-air resistance (usually 1/4Av^2) therefore a=g-1/4m*Av^2
I'm sorry, I don't possess the knowledge to understand your terminology LOL; I'm pretty bad at science and only in year 10 xD.
But thanks for your help anyways!
 

2kill4ad

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Well consider the egg as a point source. The egg experiences a gravitational attraction (a force, +-mg depending upon which direction you define as positive. Basically U=mgz therefore dU/dz=mg) towards the centre of the primary mass (in this case Earth).

So what other forces does the egg experience?
-A resistive force due to air

Now when the egg hits the ground there is a transfer of energy. This collision is inelastic (completely negligable since the mass of Earth is so large, Newton's third Law). Conservation of momentum can be used to show how inelastic collision is negligable. Ptotal=P1+P2. Some energy is lost to heat, deformation etc. Impact force can be calculuted by: J= integration of Force over time.

Here's a basic outline

p.s: obviously, Fnet=ma=mg-air resistance (usually 1/4Av^2) therefore a=g-1/4m*Av^2
is this even required for the HSC

the explanation, though being good, is far to complex for most people to understand
 

addikaye03

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is this even required for the HSC

the explanation, though being good, is far to complex for most people to understand
No dude, you really get a better understanding of energy conservation in first year uni. You redefine your understanding of motion. Look at rotation motion & applications of Newton's Laws (w.r.t. mechanics) haha I'm doing the advanced physics subject at Melbourne University. I wrote it up to give a better idea. I could probably write it up alot more indepth than this though. I'll think
 
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