Let’s say you live on Planet Pseudo-Science, where “weight” can be “generated” at the drop of a hat. Well, maybe not the drop of a hat, but rather the spinning of balls in a dumbbell.
The comic book premise certainly sounds fun! Balls inside each dumbbell can be set to rotate at different speeds. The faster they rotate, the more weight is generated. Seeing as though we live on planet Earth, where a little thing called physics applies, this design, while neat looking, is about as worthless as it gets.
The law of conservation of mass says, essentially, that matter cannot be created or destroyed in a closed system. These dumbbells claim to generate weight, which is a merely a function of gravity on mass. (That’s why you’d weigh differently on other planets—the gravitational force is different, while your mass remains constant.) Long story short, the spinning balls don’t change the dumbbells’ mass, so no change in weight could happen.
And now it’s time for Poland v. Austria, two rubbish teams.
via Boing Boing Gadgets and Gearfuse
My first impression after glimpsing that photo was some kind of awesome new crayon. Someone should send that image to the good people at Crayola and tell them to innovate something new.
Hahahaha wtf CRAYONS?!?!?!
They might not add weight, but when you are exercising, weight is irrelevant. The point of the weights is to create resistance. Spinning objects do create inertia about the plane on which they are rotating. Everyone had that experiment in high school physics where your teacher spins the bicycle wheel and then tries to turn it so that the wheel is spinning vertically instead of horizontally, right? Same basic principle as a gyroscope. The spinning object resists being taken out of plane.
So, if you were doing bicep curls with these things vertically in your hand at the bottom of the rep, they’d be pretty much horizontal at the top of your rep, and at least in theory, based on how fast they were spinning, you could vary the amount of resistance to changing planes from horizontal to vertical.
It would require that you follow a pretty rigid form while doing your exercises (if you held them like traditional dumb-bells, for example, with the shaft pointing side to side in your hand, doing a curl would not take the spinners out of plane and therefore create no resistance), and the amount of inertia is dependent on the mass and diameter of the spinning object. By the looks of these things, they don’t have a large diameter (and probably don’t weigh much since they are supposed to be adjustable across a range that apparently goes down to at least 15), so in the end, your assessment that they are rubbish might be fairly accurate. But, at least in theory, they could KINDA SORTA work, without actually needing to “create mass”.
Those spinning balls would add resistance, not weight. If you take a bicycle wheel and spin it, holding it by a rod through the center, it becomes difficult to tilt left and right due to gyroscopic principles (this is why moving bikes are more stable than a stopped bike). The same thing would happen here, but you’d have to tilt the bar left and right to feel the resistance, not use it as a dumbbell.
Well, actually I tought of lightsabers
This is actually a genius idea. Physics and inertia are exactly why it WILL work. A buddy of mine uses a tool for carpal tunnel that uses this exact same technology.
I have one of those tools too, and thats what these remind me of.
Physics are the reason this is an incredible idea. The inertia of the balls spinning creates resistance to move out them out of their rotational plane. So, you are correct in saying that weight is not not generated (being that weight is the effect of gravity on mass), but there is resistance, which is all that really matters when you are trying to get sexy.
I might not be a scientist but I am a pilot and do fly aerobatics…
As soon as you redirect the aircraft out of the plane that you were flying in you are will feel positive or negative G’s.
When flying “higher G” maneuvers like a simple loop you can pull 3-4 times gravity (bottom of loop) in the aircraft and although my mass has not changed the fact that I am under the equivalent of 3 times gravity makes me feel like I am 500lbs…