HOW DO TRACTOR BEAMS WORK?

How do tractor beams work?

•Up until recently, tractor beams (beams of light that tow objects) existed only in the world of science fiction.

•While large-scale tractor beams that can tow space ships are still machines of the future, microscopic tractor beams are here today.

•The idea at first seams to defy physics. Shoot light at an object and the light's momentum should push the object away from the light source according to the law of conservation of momentum; not pull it closer like a tractor dragging its cargo.

•But what if you managed to create a situation where upon striking the object, the light gains forward momentum instead of losing it.

•In that case, the law of conservation of momentum tells us that the object will lose momentum in the forward direction, even to the point of going backwards, towards the light source.

•So there is a way to make a tractor beam without violating any physics, if you can get the light to gain forward momentum upon interacting with the object.

•You need to the light to slingshot past the object instead of bouncing off of it. The most effective method to accomplish this feat at this point in time is to use solenoidal light beams.

•A solenoidal shape is like a wire wrapped in circles into a helix that forms a hollow cylinder. But in this case, there are no wires. The light itself, traveling through the air, is formed into this hollow, spiraling shape.

•San-Hyuk Lee of UC Berkeley and his collaborators have experimentally verified that the solenoidal light shape indeed draws objects – in their case, microscopic glass spheres – towards the light source.

•They have therefore successfully created a real tractor beam.

•You can think of the spiral-shaped light beam as a screw that twists the object up the beam.

•Only microscopic objects have been tractor-beamed so far because light carries so little momentum.

•In order to tow large objects, you would need very strong light beams. So strong, in fact, that damage of the object may become a problem. Research is ongoing.

Comments

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Here telecom operator are very clever, b ecause telecom operators want to earn money of 13 months instead of 12 months. Let do the calculation and find out why telecom operators are offering 28 days validity. Each month they get 2 days more, therefore in a year they get additional 24 days. There are 7 month which has 31 days so they get additional 7 days.Now in case of February ,it has only 28 days not 30. So the total number of days they get are=24+7-2=29 days. So if you recharge 12 times then more 29 days are left in a year.🤔🤔 Means for another 29 days you have to recharge from that telecom operator.😫😫 So you have to recharge 13 times in a year instead of 12 times in a year. So telecom operators provide 28 days validity only. First one telecom operator started and then another telecom operators also understood this concept and they also applied 28 days validity both in data packs and voice packs.😱😱😱

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