what is the weight of ray of light?
In Euclidean space-time...yes light does have mass. It has zero rest mass...but it doesn't exist at rest. Special relativity equations yield a relativistic mass increase to 0/0 as it approaches the speed of light, and 0/0 can equal any finite number. We know an equation of m=h*f/c^2 for it to have because we can also look at mass-energy equivalence as well as relativistic momentum to determine its effective mass when at the speed of light. Light exhibits both inertia AND participates in gravitation, and we have measured this in experiment for confirmation, hence it has mass, and weight if nearby a gravitational field. We know it has inertia because of the phenomena of radiation pressure. We know it has participation in gravity because of the phenomena of gravitational lensing of distant starlight around our sun. What is a ray of light specifically? What is its population of photons? What is its intensity? If you want to speak about the smallest unit you can even call light, that is one photon. Its effective mass depends on its frequency, and can be calculated as: m = h*f/c^2 And its effective weight in Earth's gravity: W = h*f*g/c^2 For single photon of green light at 600 THz, this yields: m = 4.42*10^(-36) kg Weight in Earth gravity: W = 4.33*10^(-35) Newtons
Light has no resting mass but since photons are never at rest there is some mass which is why it's effected by gravity.
Light doesn't have mass or weight. That's why it is able to travel at the speed of 186,000 miles per second. If light had any weight, it would take infinite energy to get it to the speed of light. And the faster you go, the heavier you become.
Light has no mass. No mass, no weight.
Depends on what you mean exactly. Photons of light have no mass. However, they do carry momentum, and light falling on a surface exerts radiation pressure. You could use this effect in space to drive something with a solar sail, using nothing for power but the sun's radiated light.
