SPEED OF DARKNESS?
IN PHYSICS I OFTEN GET STRUCK OF A QUESTION OF NOT A SINGLE TEACHER OR MY FRIENDS COULD ANSWER ME THE QUESTION IS THAT
“IF SPEED OF LIGHT IS 3 x 108 METRE PER SEC, THAN WHAT IS THE SPEED OF DARKNESS????….”
Asked 
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Categories: interesting question, Interesting Questions Tags: albert einstein, Dark energy, Dark Knight Rises, darkmatter, earth, education, Milky Way, Physics
Does gravity travel instantaneously?
Does gravity travels instantaneously? Or it travels equal to the speed of light.
Answer:
No clear answer now. If we believe in the Theory of relativity, Gravity (Gravitational Waves travel with the same speed as that of light in vacuum. If gravitons are like photons, then it makes sense too.
However I invite you to think more and post your thoughts as comments here. Let the discussion begin.
I found the following links to know more
- http://metaresearch.org/cosmology/speed_of_gravity.asp
- http://en.wikipedia.org/wiki/Speed_of_gravity
- http://www.desy.de/user/projects/Physics/Relativity/GR/grav_speed.html
Categories: +2 Physics, General Physics, Gravitation, interesting question Tags: answer, Auto, desy, discussion, Draft, Gravitational, gravitational waves, photons, speed, speed of gravity, theory of relativity, waves
Why protons attract inside a nucleus?
What is the reason for proton- proton attraction inside the nucleus according to nuclear physics? (Sanjeev Asked)
Answer: Inside the nucleus where the nucleons are very close to each other, the force which holds them together is the nuclear force, which is the strongest force in nature. The electrostatic force between protons is negligibly small compared to the nuclear force. But the nuclear force is of a very short range, 10^-15 m.
The nuclear force is charge independent, i.e; the nuclear force between proton and proton, proton and neutron as well as neutron and neutron are almost the same.
Yukawa’s meson theory suggest that the nuclear force is an exchange force. The nucleons are bound because of constant exchange of the mesons.
The nuclear force is only felt among hadrons. At small separations between nucleons (less than ~ 0.7 fm between their centers) the force becomes repulsive, which keeps the nucleons at a certain average separation, even if they are of different types. At distances larger than 0.7 femtometer (fm) the force becomes attractive between spin-aligned nucleons, becoming maximal at a center-center distance of about 0.9 fm. Beyond this distance the force drops essentially exponentially, until beyond about 2.0 fm separation, the force drops to negligibly small values.
At short distances (less than 1.7 fm or so), the nuclear force is stronger than the Coulomb force between protons; it thus overcomes the repulsion of protons inside the nucleus.
However, the Coulomb force between protons has a much larger range due to its decay as the inverse square of charge separation, and Coulomb repulsion thus becomes the only significant force between protons when their separation exceeds about 2 to 2.5 fm.
(There are many terms introduced in the explanation. You can discuss them as comments for obtaining further details, if required)
Reference:
Categories: +2 Physics, Answers, ANSWERS TO QUESTIONS FROM VISITORS, Chemistry, interesting question, Interesting Questions, Nuclear Physics Tags: answer, attraction, coulomb, coulomb force, coulomb repulsion, femtometer, Force, meson, meson theory, nuclear force, nucleus, Physics, proton, range, reason
Super Hero crossing Mach1 speed and then?!!
Charles posted this interesting Question on a Super Hero crossing the Mach 1 Speed. Visitors are requested to respond with your ideas. “I’m working on a novel with a “superhero” protagonist. The guy puts on his spandex, and takes off across state, say. OK, as he speeds up, can he tell when he approaches and ...Read the full post
Categories: Ask Physics, fiction, interesting question, Interesting Questions, mach1, novel, super hero Tags: sound
