relax, i didnt say ur wrong. I was only saying i wasn't wrong either.I suggest you google it before you get yourself even more messed up...
The conservation of momentum is similar to the conservation of energy theory in that they both deal with ideal conditions and have both mass and velocity in them but the conservation of momentum theory IS NOT based on the conservation of energy theory.
kinetic energy …
is a scalar.
momentum …
is a vector
kinetic energy …
is not changed by a force perpendicular
to the motion, which changes only the
direction of the velocity vector.
momentum …
is changed by any force, since a change
in either the magnitude or the direction
of the velocity vector will result in a
change in the momentum vector.
kinetic energy …
is always positive, and cannot cancel
out.
momentum …
cancels with momentum in the opposite
direction.
kinetic energy …
can be traded for other forms of energy
that do not involve motion. KE is not
a conserved quantity by itself.
momentum …
is always conserved in a closed system.
kinetic energy …
is quadrupled if the velocity is doubled.
momentum …
is doubled if the velocity is doubled.
So even though the equations are similar, one is not based on the other.
http://www.lightandmatter.com/html_books/2cl/ch04/ch04.html
Now I may not be as strong on the dynamics side of physics since I went into civil engineering instead of mechanical engineering but I'm no slouch at it.
I suggest you google it before you get yourself even more messed up...
The conservation of momentum is similar to the conservation of energy theory in that they both deal with ideal conditions and have both mass and velocity in them but the conservation of momentum theory IS NOT based on the conservation of energy theory.
kinetic energy …
is a scalar.
momentum …
is a vector
kinetic energy …
is not changed by a force perpendicular
to the motion, which changes only the
direction of the velocity vector.
momentum …
is changed by any force, since a change
in either the magnitude or the direction
of the velocity vector will result in a
change in the momentum vector.
kinetic energy …
is always positive, and cannot cancel
out.
momentum …
cancels with momentum in the opposite
direction.
kinetic energy …
can be traded for other forms of energy
that do not involve motion. KE is not
a conserved quantity by itself.
momentum …
is always conserved in a closed system.
kinetic energy …
is quadrupled if the velocity is doubled.
momentum …
is doubled if the velocity is doubled.
So even though the equations are similar, one is not based on the other.
http://www.lightandmatter.com/html_books/2cl/ch04/ch04.html
Now I may not be as strong on the dynamics side of physics since I went into civil engineering instead of mechanical engineering but I'm no slouch at it.
True... what happens before and after is not as important as at moment of impact.Badminton is different than tennis, tennis is use swing as i know, but badminton, what i learn is using strike.
In badminton swing will waste energy and the contact point between the shuttle and racket is very important
In this particular case, with all things being equal (racket, string, tension) then a faster swing will produce a harder/faster smash.
thx for pointing this out. I didn't want to push hard to counter debate the weakness of using conservation of momentum which druss is so fond of. In the real world shuttle making contact with racket and stringbed, there is a dwell time of contact. Within the dwell contact time the shuttle is under hard acceleration. The shuttle is never under constant velocity during contact dwell time. Upon exiting the stringbed, the shuttle is under deceleration. So at contact and after contact, the shuttle is and never under a fix velocity. The racket speed is also never under constant velocity before, during and after shuttle contact. Hence the mv components or conservation of momentum, can not express or capture this interaction properly.sure. if we have 2 moving racket of the same mass, one is faster, then the faster one will produce a harder smash.
however, what is not kept constant is the strength of the player, in order to produce a faster swing, the strength of the player must be increased, which contradicts the "all things being equal" condition.
the real question is then, if we keep the player's strength constant as well, then what is the maxima point for harder smash?
i think the answer is somewhere between very light and very heavy. the player will have to experiment to find out.
this energy storage-release component has been discussed and explained before as well.(post #24)As Kwun wrote "as with most things in badminton, things are not so simple."
Yes, faster swing will produce more power, but there are many other factors:
1. It should not be a constant swing because then the power is not maximized. As ZJH said in his training video, it is the swing during impact that is crucial. That is why proper wristwork is needed, or what elvinteh said "strike". Eg. If I swing a whip at a constant speed, it is not going to cause as much pain than if I (for lack of a better word) whipped it at the moment of impact. If fact a pro tried to teach me how to whip my racquet, not merely turning the wrist. So technique is a crucial factor.
2. The angle of contact between the string bed and shuttle will determine power also. Some people can swing fast yet slice the shuttle, so losing power. This can be done purposely for deception.
3. The equipment must be matched to the user's ability. And it must be used properly.
a. The weight, as Kwun has pointed out, must match the user. Also the balance point. Just like a hammer. If I hold a hammer near the head, I am not going to get a hit that is as strong as if I hold it further from the head. But there is an optimum. Imagine if I can lift up a maximum of 100 kg. If You attach the 100 kg weight to one end of a meter long pole and I try to lift it up using the other end, I won't be able to do it. So, the balance point must match the weight and the user for maximum angular momentum.
b. The flexibility or stiffness of the racquet. This is because you want to build up the energy in the shaft and then release it suddenly. This is just like shooting an arrow with a bow. If I have a very stiif bow then I can hardly draw the bow back. Say I can only draw the string back 1 centimeter. When I release the string the arrow is not going to shoot far. But if I have a very thin and flexible bow, then I hardly have to use any strength to draw the string to the full. But there is very little energy stored in the bow, so when I shoot the arrow won’t go far either. I need a bow which will bend to the fullest yet it is just stiff enough that it needs all my strength to do it. Then it will fly the farthest. But if you are stronger than me, then you can shoot further if you use a thicker and stiffer bow. . However, you may be a strong man and can swing your arm fast but you throw the arrow, you won’t be able to throw the arrow far; this is using your strength and releasing it in a constant velocity. So, in badminton when you swing, you are trying to flex the racquet thus storing energy in the shaft (this is like pulling on the string of the bow). But this has to be released in as short a time as possible during impact, not before or after.
c. The string bed and the frame will also affect the power of the stroke. Again, the elasticity and tension of the string, and the stiffness of the frame will determine how much “trampoline” propulsion is transferred to the shuttle.A little baby on a very tight and heavy trampoline is not going to move the bed at all. A big and heavy giant on a very elastic and loose trampoline is going to cause the whole bed to sag down and then there is not enough stored tension to even lift him up. Imagine a third person on a trampoline that matches his jump and weight. If then these 3 persons jump on their respective trampoline with the same speed, the baby will hardly bounce up, the giant will sink and not get up, but the third person will be propelled the highest.
So many people have asked for recommendations on specific brands and models of racquets for themselves. That is a wrong concept. You see pros that can flex their racquets and hit tremendous smashes. But not everybody have the same strength, swing and techniques to do what the pros do. That is why even pros use different models (and subject to their sponsors).
To get more power, you need to take care of the many factors that contribute to it, not just swing speed. When you swing, you want to store that energy into the shaft by flexing it ( just like pulling on the string of a bow) and then releasing it in a explosive way when contacting the shuttle. This is to maximize your stroke and get maximum power.
this energy storage-release component has been discussed and explained before as well.(post #24)
http://www.badmintoncentral.com/forums/showthread.php?t=79268&highlight=bow&page=3
Yes, but one can only swing the racket only so fast... there is a terminal speed at which point the muscles can only contract so fast, regardless of how light the racket is.It's kind of common sense, but yes, swing faster does make the bird fly faster. That's why you swing with a lot of force to produce a powerful smash, and you control your strength to get a nice dropshot that lands in the forecourt.