Newton's laws of motion

[Coach is Back!]

Ok - I played football in high school, lets get in some other details.... lol

The two players won't be running into each other standing upright...

The O lineman will hit with his shoulder.... so  I need to know what his shoulder measurements are (roughly) and we will only use one side of his shoulders since thats what he'll be hitting with....

The running back will most likely absorb the hit with his abs or waist... so would be a good idea to know what his waist measures... unless he crouches down and delivers a hit with one of his shoulder pads - so then we'd need to know his shoulder measurements.

Give me some rough numbers here and I could translate it into Pounds per square inch for you.

True, it would be multiple. But for the sake of argument, I'm using one as an example.

[Coach is Back!]

Coach, I have serious doubts that showing some parents physics breakdowns, will land you a client.

This is to the parent(s) of an existing client. Every so often we hold seminars to help explain our programs. Using examples like this helps explain the "why's" of our program. Although, it would be impossible for ME to go into the detail that BIG ACH is explaining. This is good stuff right here.

[cephissus]

I agree, but... "make things as simple as possible, but not simpler."

To stay on topic: There are two different scenarios after you tackle someone in football, from a physical point of view.

Either the bodies stick together after the collision (which is the case, most of the time, in football, e.g. inelastic collision) or they bounce off of each other (elastic collision).

Since the first case is much more common, here's all you need to know about it:

m1 * v1 + m2 * v2  = (m1 + m2) * vfinal

For example:

Before the collison:

Player 1 (mass = 80 kg) ---- (22 m/s) -->           <-- (-4m/s)---- (mass = 120 kg) Player 2

----> positive x-Axis

After the collision:

vfinal = (m1*v1 + m2*v2) / (m1 + m2) = (80*22 + 120*-4) / (80 + 120)  = 6.4 m/s (in positive x-Axis) -> Player 1 is overrunning Player 2.

                                                                 --- (Player 1 + Player 2  = 200 kg)----- (6.4 m/s) --->

If vfinal is negative, Player 2 will overrun Player 1.

That's really as simple as it gets. Now you can calculate how fast a lighter Player has to run to stand a chance against a much heavier Player.


** had to change / to * before vfinal

where have you been?

[BIG ACH]

Ok....

Say the impact area is 50 sq/inches...

Then your Pounds per square inch (PSI) is:  415.55 lbs per 50 sq inches...

Or 8.311 lbs per sq. inch


Coach you have to remember, force of impact (like car crashes) are not measured in PSI... they are measured in Force (Newtons or Pounds-Force as stated earlier), which is why we calculated how long the collision took place.  

Its hard to calculate this on paper, but The size of the player will positively increase force, the bigger he is, the higher the force, but it will most likely also take longer to stop him (time of collision), and the longer the time of collision is, the less force there will be experienced by said player.

[a_ahmed]

no, friction is already factored into the velocity, it won't effect the force of collision

affect 

[cephissus]

This is to the parent(s) of an existing client. Every so often we hold seminars to help explain our programs. Using examples like this helps explain the "why's" of our program. Although, it would be impossible for ME to go into the detail that BIG ACH is explaining. This is good stuff right here.

so you want to shoot off a bunch of rapid-fire figures to bamboozle them into giving you money?




but really, you know F = MA -- if your goal is to explain to parents why kids need to "be explosive", why not just say,

"Force equals mass times acceleration.  So, if your son has less mass than the opposing lineman, he needs to accelerate more in order to match the lineman's force output.  Here's how our training system can maximize your son's acceleration potential... [insert bullshit training explanations here ]."

imo, this would be a much clearer and more straightforward way of convincing parents than trying to walk them through some sort of worked out equation which you don't even fully understand yourself.

[BIG ACH]

affect 

auto correct on my phone (dunno why) bitch!  

[BIG ACH]

so you want to shoot off a bunch of rapid-fire figures to bamboozle them into giving you money?




but really, you know F = MA, if your goal is to explain to parents why kids need to "be explosive", why not just say,

bingo - simple and to the point...

Bigger players, and faster players will generate more force!

[BIG ACH]

Coach here is a video that goes into some details behind the physics of a football tackle

[Mr Nobody]

Thats funny, that was actually my first car..hahahahaha. A 74' Pinto

Is this it? I got the Title work on it.

[tu_holmes]

bingo - simple and to the point...

Bigger players, and faster players will generate more force!

Read WAY earlier in the thread... It was said previously.

[Coach is Back!]

Is this it? I got the Title work on it.

Similar. It was a gold color. You have MY original title??

[HockeyFightFan]

This is to the parent(s) of an existing client. Every so often we hold seminars to help explain our programs. Using examples like this helps explain the "why's" of our program. Although, it would be impossible for ME to go into the detail that BIG ACH is explaining. This is good stuff right here.

Then Google-Fu the physics of a football tackle and read up.

Big Ach is close but he has left out the element of Impulse in a tackle. You'd think a suicide bomber in training like Toucan Sam would know better.   

Forget all this math nonsense Chico, just tell the kids to take the shortest distance to the ball carrier, get there as fast as possible, and arrive in ill humor. They'll get it.   

[Mr Nobody]

Similar. It was a gold color. You have MY original title??

Yea I got it.

[BIG ACH]

Then Google-Fu the physics of a football tackle and read up.

Big Ach is close but he has left out the element of Impulse in a tackle. You'd think a suicide bomber in training like Toucan Sam would know better.   

Forget all this math nonsense Chico, just tell the kids to take the shortest distance to the ball carrier, get there as fast as possible, and arrive in ill humor. They'll get it.   

my whole formula was based on impulse homie!!!

[HockeyFightFan]

my whole formula was based on impulse homie!!!

There will be no partial credit for 35 year old Arab "students" with expired visas and a C4 laden vest hanging in their closet.   

Beak Ach!   

[BIG ACH]

There will be no partial credit for 35 year old Arab "students" with expired visas and a C4 laden vest hanging in their closet.   

Beak Ach!   

lol

I'm American homie - Proud and free! 

[HockeyFightFan]

lol

I'm American homie - Proud and free! 

So what makes you American....the 14-inch arm or the 87% bodyfat?

You look like the kind of guy that drycleans his underwear.
 

[BIG ACH]

So what makes you American....the 14-inch arm or the 87% bodyfat?

You look like the kind of guy that drycleans his underwear.
 

Well, my naturalization certificate for starters...  


And no... your mom prefers to lick the inside of my underwear clean for me when called upon!  So no need for dry cleaners!  

 

[HockeyFightFan]

Well, my naturalization certificate for starters...  


And no... your mom prefers to lick the inside of my underwear clean for me when called upon!  So no need for dry cleaners!  

 

Naturalization certificate? You marry Tbombz for a green card?

1981 called and said Lionel Ritchie wants his hair back...
 

[Coach is Back!]

Thanks guys for help on this, it really helped figure some things out. This is the kind of stuff that isn't touched upon when I go to seminars or clinics and have never heard this question asked at one. Thanks again.

[BIG ACH]

Naturalization certificate? You marry Tbombz for a green card?

1981 called and said Lionel Ritchie wants his hair back...
 

Yeah I got nothing for that   


TBombz was willing... I couldn't resist!  LOL

[HockeyFightFan]

Yeah I got nothing for that   


TBombz was willing... I couldn't resist!  LOL

I know.....I saw your blushing bride Facebook updates.

So what exactly is this "felching" you guys keep referring too?

[240 is Back]

Hit in order

4, 1, 2, 3.

[HockeyFightFan]

Thanks guys for help on this, it really helped figure some things out. This is the kind of stuff that isn't touched upon when I go to seminars or clinics and have never heard this question asked at one. Thanks again.

Coach, keep in mind, football tackles (collisions) are different than a car crash between two inanimate objects. Watch video of Bo Jackson, Earl Campbell , or John Riggins to see that power, speed, balance and leg drive will go a long way in determining who comes out on top in an on field collision.