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Yes. In a vacuum, the only resistance is the friction in the suspension for the bob of the pendulum. Other than that, it should swing a long time. In air, friction with air will add to the friction in the suspension and it won't swing as well as it would in a vacuum. But it will swing for a while. A pendulum will swing in water, but the hydrodynamic drag will make it stop in a really, really short period of time. Just a couple of swings will strip the pendulum of almost all its energy. And the speed of the pendulum will be slower than in air, and it won't swing anywhere nearly as far through the bottom of its arc as it did in air.
Wiki User
∙ 15y ago
Wiki User
∙ 11y agoIn an idealized thought experiment, yes, but in the real universe NO.
In the real universe the energy of the motion of the pendulum will be dissipated by friction and deformation
- It is impossible to acheive a perfect vacuum so there will always be some residual gas molecules to collide with the pendulum and slow it down - dissipating the energy as heat
- The pendulum must be attached to a pivot poiint, which will never be frictionless - thus dissipating the energy as heat. Note that if the point of attachment is rigid, the line connecting the attachment point and the end of the pendulum would have to flex - disspating energy as heat when it did so due to imperfect elastic deformation
- Since no pendulum is perfectly rigid, the line connecting the end of the pendulum to the pivot point (or attachment point) will stretch and relax alternately - even if only by an amount not visible to the eye. This will dissipate energy as heat. The end of the pendulum will also deform as it swings through each cycle - again. Dissipating the energy as heat.
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Is it possible to have motion in absence of force?
Not according to Newtons Law: Forces = Mass X Acceleration However, in a vacuum, after you used your force on an object and it now has motion, the object will have motion for eternity, even when there is no force. So as a matter of fact, it is possible. Just not on any planet, only in outer space.
Why might you say the solar system is mostly 'empty space'?
Everything is mostly space. The diameter of the sun is 865 thousand miles, which is a bit under a million. The radius of the earth's orbit is 93 million miles, almost 100 million. Sedna, which isn't even outside the solar system, orbits 900 times as far (currently).
What are the gases contained in a vacuum?
Theoreticaly there are no gasses in a total vacuum
What is a volume empty of free molecules?
a vacuum
How many inches of vacuum equals 10 mm of hg?
If it is a perfect vacuum, any amount of it will have zero pressure.If it is a perfect vacuum, any amount of it will have zero pressure.If it is a perfect vacuum, any amount of it will have zero pressure.If it is a perfect vacuum, any amount of it will have zero pressure.
What conditions would have to exist for perpetual motion to be possible?
No friction, in other words a vacuum.
Why can't perpetual motion work?
Perpetual motion would only work in a perfect environment - perfect vacuum - zero friction, zero resistance. The best we can hope for is to minimize the input energy - increase efficiency...
How is a vacuum achieved?
Vacuum is achieved by removing air in a certain space
Why is perpetual motion difficult on Earth?
You need a frictionless mechanism for perpetual motion. Even with zero contact, the atmosphere itself exerts friction. If you were able to devise a zero contact mechanism in a vacuum, you would still need a propulsion system that would create as much energy as it uses, so far this is not possible.
How can pendulum oscillate in vacuum even there is no gravity?
There IS gravity in a vacuum - there's no AIR.
Is a feather falling in a vacuum projectile motion?
A feather falling in a vacuum is not considered as a projectile motion. Gravity, which is absent in a vacuum, is one of the components of projectile motion.
What would happen if a pendulum is set to swing in vacuum?
it will not stop forever
Can a pendulum swing in vacuum?
Yes. The swing of a pendulum is caused by gravity acting on the mass of the pendulum. Actually, enclosing a pendulum in a container and removing all the air inside (thus creating a vacuum) would actually help the pendulum to swing for a longer period of time. That's because air creates drag on the moving mass, slowing it down. Think of a person trying to walk into a stiff breeze. Slows you down, right? The same thing happens to the pendulum as it moves through the air. Now, if by vacuum you really meant out in space where there is no air, that's a different situation. There is no (or very little) gravity in space, when you are not on or near a large body such as a planet. A pendulum in space would not work due to the lack of gravity there.
Do simple pendulum vibrates in vacuum?
It does oscillate. We have to use the word 'vibration' if the amplitude of oscillation is very very low. The prong of a fork vibrates. But simply pendulum oscillates.
Is the ending and starting height of the pendulum exactly the same?
No, the swing of the pendulum will never carry it back quite as high as it was when it started. The pendulum must work against air resistance, and so a little bit of momentum is lost with every swing. Even if the pendulum operated in a vacuum, there would still be some tiny amount of friction at the point where the pendulum is attached to its frame. The swing of a pendulum is never 100% efficient. So the pendulum will run down.
Explain why perpetual motion is impossible?
The secret is, it's very possible! Perpetual motion has been here for 2 decades! It has been perfected. The government doesn't want the public to know. The oil companies are very powerful as well. Free energy will create war. I left the above intact because I believe in free speech - even if it is complete horse manure like the statements above. There are two types of "perpetual motion" machines - those that don't work because they try to violate the 1st law of thermodynamics (energy cannot be created or destroyed - it can only change form), and those that don't work because they try to violate the 2nd law of thermodynamics (heat only flows spontaneously from hot to cold). The only conspiracy is the laws of the universe operating to expose con artists who try to get people to give them money for something of no value. The reason that perpetual motion is impossible is that there just isn't any situation where friction and gravity don't operate. Note that gravity is primarily an issue for any imagined perpetual motion machines that would try to operate out in the near-vacuum of space. Some work always has to be input to a system to keep the motion going to overcome the friction. That energy has to come from somewhere and a closed system only has a finite amount of energy - eventually all the motion will be converted to heat via friction and the motion will cease. You just can't get more energy out than you put in. Some perpetual motion machines claim to be able to suck energy from their surroundings, but you can only absorb heat from the surroundings as long as you are cooler than your surroundings. Eventually you warm up to the same temperature as the surroundings. There are some energy producing systems that take advantage of naturally occurring temperature differences but they are not perpetual motion machines. They still rely on the input of energy from somewhere, whether it be geothermal or solar.
Why does a ideal pendulum swing back and forth indefinitely?
An ideal pendulum is one in which no air resistance or friction is present. Hence when set into motion it never loses energy to it's surrondings. So when released, and left to swing, the energy potential it had get's convertedinto kinetic energy and therefore the pendulum swings. When it reaches it's amplitude(Highest swing) the energy is converted back to potential, and as it falls back to kinetic. As it is "ideal" it never loses energy to heat/ friction. Therefore, the conversion of kinetic energy to potential etc etc will always be constant and it will never stop. Although in reality it is impossible to have an "ideal" pendulum, near ideal ones can be obtained by suspending the pendulum in a vacuum.
