A Mistake 99% Badminton Stores Are Making

[magiadam]

Whenever they describe the weight of the racket, it is described with a unit of 'Grams' or 'Lbs', when it should be expressed with a unit of 'Newtons' since they're talking about the weight technically. They should express the racket's mass properly.

Just a thought XD

[Tsumaranai]

Um.., mass is not the same as weight. Weight is relative to gravity, and will be what you feel. Mass is the measurement of the amount of matter. Also, mass is expressed in grams...

[magiadam]

But my point is, if they express in Weight, they must use a unit of force, such as Newtons.

[Tsumaranai]

But they're not... They're measuring the mass.

[magiadam]

But they're not... They're measuring the mass.

Then it should be:

"Mass: XXX Kg"

instead of

"Weight: XXX Kg"

[jerby]

weight is a force, and indeed has the unit of newtons.
Mass however is an (extensive?) property, and has a unit of grams or pounds.

Also, just for poops and giggles... weight is not only dependend of the gravity, it is depended on all the forces acting on the object.
a 5kg table is acting on the floor with a weight of roughly 50N, whent he table is left standing. but when I lean on it with a 100N force the table is acting on the floor with a weight of 150N.

But it's such a common misconception everybody knows what is meant...
Our site happily states weight :p

(I guess this removes any doubt people had I was a geek, now they know for sure ;))

[Fidget]

But my point is, if they express in Weight, they must use a unit of force, such as Newtons.

Force is mass times acceleration. (kg*m/s2)

If you consider that the earth is pulling the racquet's mass at all times downward, I guess you could certainly describe it in Newtons....and that would be handy... when?

You: "Hey doc, my buddy dropped his 0.090kg racket on my head at 9.8m/s2 meaning I sustained a 0.882 Newton force to my forehead."
ER doc [busy stitching] "Mm, thanks for that Sport. Now just sit still, that's a good lad."

[Tsumaranai]

Now there's the argument you were going for.

Well, we're talking about "empty" weight, without other forces acting on the object besides gravity. Of course, that's not technically weight. Weight is one property, while another force is not considered the weight, as it is the addition of the weight of another object while there is also work being done on the object if you were to lean on it.

[Fidget]

Now there's the argument you were going for.

Well, we're talking about "empty" weight, without other forces acting on the object besides gravity. Of course, that's not technically weight. Weight is one property, while another force is not considered the weight, as it is the addition of the weight of another object while there is also work being done on the object if you were to lean on it.

That's as clear as mud:)
Simply put, the weight is the force the Earth has on an object's mass.

[cooler]

Whenever they describe the weight of the racket, it is described with a unit of 'Grams' or 'Lbs', when it should be expressed with a unit of 'Newtons' since they're talking about the weight technically. They should express the racket's mass properly.

Just a thought XD
u must be a newton fan:p

[Fidget]

u must be a newton fan:p

Me too. I loved her in 'Grease'!

[cooler]

Me too. I loved her in 'Grease'!
oh? i thot she's a neutron bomb:D

[jerby]

Simply put, the weight is the force the Earth has on an object's mass.

weight is the force than one body acts on another (a rock lying on a table outs weight on the table)
the force the earth has on an object is called gravity
;)

[Pete LSD]

Long lived Newtonian mechanics :)!!!

[Fidget]

Thanks Jerby. I stand corrected.:o
Who would have thunk that BC could be so educational?

[Tsumaranai]

That's as clear as mud:)
Simply put, the weight is the force the Earth has on an object's mass.

Ok, well, to clarify: The "weight" weight of an object is generally considered to be just the object and the force of gravity upon the object. If you were to lean on a table, you are not merely placing your weight and adding to the force the table is exerting on the ground. You would be imparting energy and thus doing work. You would first have to calculate work before you add that additional force. If you placed a book upon a table, I would not call that the weight of the table. I would say that there's the weight of the table and the weight of the book, or else the weight of the table in addition to the force exerted by the book upon the table. I wouldn't combine individual weights to be considered as a number that represents both objects, such as was done with the table and the leaning.

[cooler]

weight is the force than one body acts on another (a rock lying on a table outs weight on the table)
the force the earth has on an object is called gravity
;)i believe in a newtonian world, both reference objects of mass are attracting to each other. ie, the racket mass is pulling onto earth's mass too.

[Pete LSD]

There is certainly potential energy with the person placing his weight on the table. If the person's feet slipped and fell (PK his/her face on the table), the drop in height is the change in potential energy translated into kinetic energy. Ouuuccchhhh, what a painful way to experiment with Newtonian mechanics :D.

[Pete LSD]

Yes and the Earth's mass is just overwhelmingly huge :D.


i believe in a newtonian world, both reference objects of mass are attracting to each other. ie, the racket mass is pulling onto earth's mass too.

[cooler]

There is certainly potential energy with the person placing his weight on the table. If the person's feet slipped and fell (PK his/her face on the table), the drop in height is the change in potential energy translated into kinetic energy. Ouuuccchhhh, what a painful way to experiment with Newtonian mechanics :D.that is why it is better and simplier to express the racket in gram, not in newton.:D

[Tsumaranai]

i believe in a newtonian world, both reference objects of mass are attracting to each other. ie, the racket mass is pulling onto earth's mass too.

Then'd we'd have to consider the gravitational pull of the sun, as well. What messy business!

[cooler]

Yes and the Earth's mass is just overwhelmingly huge :D. it takes minimum of 2 to tangles in the context of attraction

[Pete LSD]

Now, don't jump into relativity where the gravity of an object warps space and time around it. :p:D


i believe in a newtonian world, both reference objects of mass are attracting to each other. ie, the racket mass is pulling onto earth's mass too.

[Pete LSD]

It is a messy business if one were to travel to Mars or other planets within our solar system. Okay, we are off topic. Let's discuss this in Chit Chat.


Then'd we'd have to consider the gravitational pull of the sun, as well. What messy business!

[cooler]

Then'd we'd have to consider the gravitational pull of the sun, as well. What messy business!
again, that is why expression in newton is vague, it changes constantly even if the racket is not moving

[Fidget]

Now, don't jump into relativity where the gravity of an object warps space and time around it. :p:D

Yikes! This is geekily turning into a Star Trek convention.
Beam me out of here, Scotty!

[cooler]

Now, don't jump into relativity where the gravity of an object warps space and time around it. :p:Dno gravity can warp space and time like your mind pete;):D:D:p:p:cool:

[Pete LSD]

Let's discuss Newtonian mechanics here: http://www.badmintoncentral.com/forums/showthread.php?p=844527#post844527

[wocdam]

another point to ponder. since every racket has a different CG (centre of gravity), how is it possible for the racket to be measured to the accuracy of 0.1grams? electronic balance will give a difference of 0.3grams when the racket is placed at different positions on the balance. unless they hang the racket from the tip and weigh them, then it may not be so accurate after all.

[Tsumaranai]

Well, now we can just simply say that the range for the mass is because of the slightly varying amount of material in each racket that they can't control to the nearest .1 grams.

[magiadam]

Mass does NOT equal Weight -___-

Mass is expressed in Kilograms or Grams.
Weight is expressed in Newtons.

Get your units right >__>

[Tsumaranai]

Who exactly are you referring to?

[magiadam]

Who exactly are you referring to?

Anybody who claims Weight is expressed in KiloGrams or Grams.

[kwun]

racket should be expressed in mass. the reason is simple. not only are we interested in how heavy the racket weighs on a scale, whose weight we can calculate by f=ma, we are also interested in how much force we need to accelerate the racket, which is more accurately expressed in mass, also due to f=ma.

so in other words, 99% of the stores out there are giving us the correct units, but not the correct label.

[wood_22_chuck]

I would think the majority of buyers would just go:

XXXX: 90-94 gms

ahh, perfect, that's the right one. Now, which color grip should I choose?

and ponder no further than that.

-dave

[magiadam]

racket should be expressed in mass. the reason is simple. not only are we interested in how heavy the racket weighs on a scale, whose weight we can calculate by f=ma, we are also interested in how much force we need to accelerate the racket, which is more accurately expressed in mass, also due to f=ma.

so in other words, 99% of the stores out there are giving us the correct units, but not the correct label.

Thank you for the first person that finally understands me.

[martin8768]

no showing the mass of the racket would be a big FAIL. no body is interested in knowing how much mass a racket has, we want the weight of the racket. using newtons is only for expressing forces in a scientific context. using grams is practical and straight to the point.

[magiadam]

no showing the mass of the racket would be a big FAIL. no body is interested in knowing how much mass a racket has, we want the weight of the racket. using newtons is only for expressing forces in a scientific context. using grams is practical and straight to the point.

Wow man, you haven't read every post before you answered had you?

[cooler]

Whenever they describe the weight of the racket, it is described with a unit of 'Grams' or 'Lbs', when it should be expressed with a unit of 'Newtons' since they're talking about the weight technically. They should express the racket's mass properly.

Just a thought XD

lbs is reference to force already as we don't say lbs mass.

we dont necessary have quote it in newton, expression in gram-force is suffice but we just lazy, and say 'gram' for short.

[ScubaSteve]

I would think the majority of buyers would just go:

XXXX: 90-94 gms

ahh, perfect, that's the right one. Now, which color grip should I choose?

and ponder no further than that.

-dave

^yup, or thats at least how we pick rackets around here.

I don't think anyone has really cared about this subject mainly because it doesn't matter if the companies are wrong because ALL of them are making the same mistake. :D

[magiadam]

Let's all make the first badminton store that displays "Mass: XXX grams" then ^_^

[Tsumaranai]

Well, it'd be illogical to tell us the actual weight in Newtons. The average person probably wouldn't know the Newtons to pound ratio, as I forget right now, as well. There is much more to discern from mass than weight. I doubt a racket would weigh more than a couple pounds--probably less. It's easier to convert through mass in grams/kilograms than weight in Newtons.

[llpjlau]

why do people ask you how much you weigh then? and why is it called a weigh-in on The Biggest Loser? doesn't that relate to weight?

i think you don't have to be technical about labels. i think people would love to say Weight:80g than Mass:80g.

[jchan04]

weight must have a relativity. the weight here on earth and on moon is different.
but we're playing badminton on earth (i hope) and everything is measured in kg or lbs... so let's keep that constant and try not to change anything. whatever you learnt in physics should stay in physics.

[cooler]

why do people ask you how much you weigh then? and why is it called a weigh-in on The Biggest Loser? doesn't that relate to weight?

i think you don't have to be technical about labels. i think people would love to say Weight:80g than Mass:80g.

it is not wrong.
if a racket weights 90g, it is 90g force because it is a weight measured by a weight scale, same way if the same racket was weighted on a imperial scale which will read ounces or 3.2 oz or .199 lb. No weight scale sold ever divide the 90g by gravity to give u a mass reading.

ie thread is pointless

[cooler]

why do people ask you how much you weigh then? and why is it called a weigh-in on The Biggest Loser? doesn't that relate to weight?

i think you don't have to be technical about labels. i think people would love to say Weight:80g than Mass:80g.

it is not wrong.
if a racket weights 90g, it is 90g force because it is a weight measured by a weight scale, same way if the same racket was weighted on a imperial scale which will read ounces or 3.2 oz or .199 lb. No commercial weight scale sold ever divide the 90g by gravity to give u a mass reading.

ie magiadam thread is pointless

[magiadam]

it is not wrong.
if a racket weights 90g, it is 90g force because it is a weight measured by a weight scale, same way if the same racket was weighted on a imperial scale which will read ounces or 3.2 oz or .199 lb. No commercial weight scale sold ever divide the 90g by gravity to give u a mass reading.

ie magiadam thread is pointless

1) The thread is not pointless, it is a true error all markets are making.

2) Don't flame people

3) In the formula F=ma,

F = Force (Newtons)
m = Mass (grams)
a = Accelration (9.81 on Earth).

Weight, is a FORCE. Thus, it must be expressed in Newtons, and not Grams hence, markets are using the wrong term there buddy!! In order for markets to use Grams, they must express it by "Mass: 90 grams"; and NOT "Weight: 90 grams". Unit for Weight is NOT EQUAL TO Grams. If you were studying Sciences in University or something you'd know before you gave false information and made yourself look bad infront of the whole world.

Point brought out.

[kwun]

1) The thread is not pointless, it is a true error all markets are making.

2) Don't flame people

3) In the formula F=ma,

F = Force (Newtons)
m = Mass (grams)
a = Accelration (9.81 on Earth).

Weight, is a FORCE. Thus, it must be expressed in Newtons, and not Grams hence, markets are using the wrong term there buddy!! In order for markets to use Grams, they must express it by "Mass: 90 grams"; and NOT "Weight: 90 grams". Unit for Weight is NOT EQUAL TO Grams. If you were studying Sciences in University or something you'd know before you gave false information and made yourself look bad infront of the whole world.

Point brought out.

i am just curious. if a friend asks you how much you weigh, what do you answer? answer me honestly...

[silentheart]

i am just curious. if a friend asks you how much you weigh, what do you answer? answer me honestly...
Sorry Kwun, You asked for it.
Which one? Net weight? Gross Weight? Girly weight? Before Badminton weight? After Badminton weight? My weight in LA? My weight in Vail?

Everything but Newton...

[jhirata]

i am just curious. if a friend asks you how much you weigh, what do you answer? answer me honestly...
I weigh 800N on earth :D (g=9.81N/KG = (9.81Kg M/S^2)kg = 9.81M/S^2)
And therefore my mass is..

W=MG
M=W/G
=800N/9.81M/S^2
=(800kg M/S^2)/9.81M/S^2
= 81.55Kg
= 815.5N?

Sorry.. I have a freaking physics test tommorow. :crying:


3) In the formula F=ma,

F = Force (Newtons)
m = Mass (grams)
a = Accelration (9.81 on Earth).

Weight, is a FORCE. Thus, it must be expressed in Newtons, and not Grams hence, markets are using the wrong term there buddy!! In order for markets to use Grams, they must express it by "Mass: 90 grams"; and NOT "Weight: 90 grams". Unit for Weight is NOT EQUAL TO Grams. If you were studying Sciences in University or something you'd know before you gave false information and made yourself look bad infront of the whole world.

Point brought out.

They may be wrong, but as long as the whole point is conveyed,( how heavy or light the racquet is ) then "99%" of the people interested in the racquet wouldn't even care about what the units are in.
Some people around the world wouldn't know the difference between mass and weight, and the unit: Newtons. Wouldn't it be easier just to measure the racquets in grams because most people know about it..
Measuring the weight and mass in Neutons just makes things complicated because everybody's used to measuring in grams, kilograms, pounds and so on outside the physics class or the exam rooms :D.

[cooler]

since difference in gravity is too small for common practical application, what object we weighs is expressed in mass, no need to multiply it by g to express it in force. That's why we call the scale weight scale, not mass scale. Without gravity, common man wouldn't able to measure what mass of a racket.

[magiadam]

Without gravity, common man wouldn't able to measure what mass of a racket.

That's not true, there's such thing as a mass scale o__o

[cooler]

That's not true, there's such thing as a mass scale o__o

like weapon of mass scale destruction?:p

can u show me a mass scale that doesn't rely on gravity 'force' for its measurement?

[llpjlau]

i would say my weight in kilograms. or in grams if anyone prefers that. but never in newtons.

[kwun]

i would say my weight in kilograms. or in grams if anyone prefers that. but never in newtons.

i think that's pretty much it. if someone ask you how much you weigh, and you answer "newton", they will have no clue what you are talking about and even if they do (i do), they won't be able to make any association easily to the unit that they are used to.

and if she is girl, she probably thinks you are a geek and walks away!

[coolhandluke]

Any übernerd worth his salt knows that the Newtons can't hold an apple to the Oldtons, which were more heavier due to ultra high magnitude gravity (UHMG). :D

[cooler]

in summary,
when u weighting in something, u r already reading it in mass unit, ie kg or lbs. It is a hassle to compare newton because we don't know what other forces are acting on that object.

same reason why we dont say kelvin for temperature in normal purpose

[kwun]

unless you are from Mars, of course.

and of course if you go around telling everybody your weight in Newton, ppl probably think you are from Mars.

[magiadam]

i think that's pretty much it. if someone ask you how much you weigh, and you answer "newton", they will have no clue what you are talking about and even if they do (i do), they won't be able to make any association easily to the unit that they are used to.

and if she is girl, she probably thinks you are a geek and walks away!

Then the person who responds is ignorant and wrong.

[jchan04]

Then the person who responds is ignorant and wrong.
magiadam... are you trying to change the system? i think ppl in general are fine with the current system of measurement.

like they say... if it ain't broken, don't fix it!

[llpjlau]

Then the person who responds is ignorant and wrong.

you wont be ignorant if they reply i weigh XX newtons and don't get what he/she says. it is just out of our daily vocabulary unless of course you are a physicist or researcher and something along those lines.

[cooler]

i think magiadam got carrried away with his new found knowledge of high school physics. Why talk about newton when mass data is more meaningful. If i give u mass data and u can't understand that, then i wonder who is ignorant and wrong.

[drifit]

silly mistake by manufacturers....
they should make a much bigger sticker to indicates the weight.
hemisphere weight = X kN
pole weight = X kN
sea level weight = X kN
100m from sea level weight = X kN
300m from sea level weight = X kN

next time, when i want to buy steel bar, i will ask them to weight it at 1000m from sea level. cause they are charging me with weight, not mass......:D

BC is very good. other than teaching me badminton, i do learn other things...:p

[cooler]

silly mistake by manufacturers....
they should make a much bigger sticker to indicates the weight.
hemisphere weight = X kN
pole weight = X kN
sea level weight = X kN
100m from sea level weight = X kN
300m from sea level weight = X kN

next time, when i want to buy steel bar, i will ask them to weight it at 1000m from sea level. cause they are charging me with weight, not mass......:D

BC is very good. other than teaching me badminton, i do learn other things...:p
don't forget the more important data, the swing weight, head balance weight

[jchan04]

i think magiadam got carrried away with his new found knowledge of high school physics.
I second to that! hhahahaha.....

[magiadam]

Whether it is more meaningful or not, therotically, you're wrong.

[llpjlau]

Whether it is more meaningful or not, therotically, you're wrong.

theoretically, you spelled theoretically wrong. frankly, do you answer XX newtons when someone asks you your weight? if you do, then you are weird. if not, i dont see what the big fuss is about.

[wood_22_chuck]

You're starting to sound like a troll, magiadam. Can you answer the query that people have been asking?

"What do you say when people ask how much you weigh?"

x Newtons, or x kgs? Either way, you're pinned down. Newtons, people think you're weird despite you think them ignorant, and if kgs, then you've just gone against your premise.

-dave

[magiadam]

frankly, do you answer XX newtons when someone asks you your weight? if you do, then you are weird.

Stereotype much?

[llpjlau]

Stereotype much?

it is not a stereotype. 99.9% of people would use kg to tell people their weight. ask anyone on BC, they won't disagree with me.

[jhirata]

it is not a stereotype. 99.9% of people would use kg to tell people their weight. ask anyone on BC, they won't disagree with me.

I'm that 0.1% who answered it in Newtons :D


I weigh 800N on earth :D (g=9.81N/KG = (9.81Kg M/S^2)kg = 9.81M/S^2)
And therefore my mass is..

W=MG
M=W/G
=800N/9.81M/S^2
=(800kg M/S^2)/9.81M/S^2
= 81.55Kg
= 815.5N?

Sorry.. I have a freaking physics test tommorow. :crying:

[2007fp]

I learn this in first year physics, this is what the prof told me, it is wrong in physics terms, but it is generally accepted in the real world therefore is right. and make keep things simplify.

[jhirata]

I learn this in first year physics, this is what the prof told me, it is wrong in physics terms, but it is generally accepted in the real world therefore is right. and make keep things simplify.
Thanks for clearing things up. That's what myself and some others were meant to say before.. :)

It's the same for English.. there's a difference between 'then' and 'than', but as long as others can understand what they mean by it, then it's not really much of a problem at all.
For example.. some people here may say: 'this racquet is better then that racquet'. We know that he or she should have used 'than' instead of 'then', but we all know what they mean and there's no need to bother them by correcting their English grammar either, so we dont.

[magiadam]

Thanks for clearing things up. That's what myself and some others were meant to say before.. :)

It's the same for English.. there's a difference between 'then' and 'than', but as long as others can understand what they mean by it, then it's not really much of a problem at all.
For example.. some people here may say: 'this racquet is better then that racquet'. We know that he or she should have used 'than' instead of 'then', but we all know what they mean and there's no need to bother them by correcting their English grammar either, so we dont.

That person, is thus, ignorant.

[cooler]

That person, is thus, ignorant.when u r older, u will see it like the rest of us:p

[MSN04]

weight is a force, and indeed has the unit of newtons.
Mass however is an (extensive?) property, and has a unit of grams or pounds.

Also, just for poops and giggles... weight is not only dependend of the gravity, it is depended on all the forces acting on the object.
a 5kg table is acting on the floor with a weight of roughly 50N, whent he table is left standing. but when I lean on it with a 100N force the table is acting on the floor with a weight of 150N.

But it's such a common misconception everybody knows what is meant...
Our site happily states weight :p

(I guess this removes any doubt people had I was a geek, now they know for sure ;))

ROFL~! Pounds is not mass, it is a force. n00b

[MSN04]

Whenever they describe the weight of the racket, it is described with a unit of 'Grams' or 'Lbs', when it should be expressed with a unit of 'Newtons' since they're talking about the weight technically. They should express the racket's mass properly.

Just a thought XD

Again... Lbs is a force. At least get the facts straight before you start a thread? :D

[MSN04]

That person, is thus, ignorant.

Totally agreed with you when people can't even tell that lb is force, not a mass, and start bragging on some internet forum. Woot.

[kwun]

this thread is getting no where with both sides not seeing (or deliberately not willing to see) the argument of the other.

closed.