It doesn't always travel in straight line! Light can be bent by objects of very large mass (for instance, when it passes by a star) by gravity. It is also bent when the medium it is passing through changes index of refraction.
Otherwise, it does travel in a straight line. Although to be honest, I'm not entirely sure "how" we know that! Good question! Anybody?
But you do know if the thing seen is really in the position that it appears to be.
How do know that it travels in a straight line?
Because people cant see around bends and you need light to see so light cannot bend
Well, I Was Wondering Exactly The Same Thing,
But I Think It Is Because If Someone Stands In Front Of A Light Source It Creates A Shadow.
Because Also If Light Could Bend Then It Could Easily Go Round That Someone Which Standing In Front Of A Light Source Thus Not Creating A Shadow.
it may be that when it travels it is not changing its medium but when changed the process is called refraction
That glass is transparent
you say light travels in a straight line
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Fireplaces have mostly radiant heat- infrared light. All light travels in a straight line- that whey the people in front feel the heat.
Light travels in straight lines. A shadow is caused when light beams hit an object and bounce off, preventing the light beams from passing through and hitting the ground on the other side. So when you, for example stand in the sun and the suns rays hit you, the light reflects off you and goes the other way. so behind you no light falls from the direct rays of the sun, so it is dark. The area around your shadow is where the light is hitting and reflecting, so technically speaking there is shadow under them, which is why we associate the ground with being dark. no light.
The imaginary line that extends straight out from the center of a reflective surface is the optical axis.
Because its probably a mirage. A mirage is an image of a distant object caused by refraction of light. The puddles on the road are light rays from the sky that are refracted to your eyes.Lets say there is a white car behind you and you notice shiny white areas behind the car. The air just above the road is hotter than the air higher up. Light travels faster in hot air. So light rays from the white car that travel toward the road are bent upward by the hot air. Your brain assumes that the rays travel in a straight line. So the rays look as if they have reflected of a smooth surface.
So it’s kind of a complicated process, but here’s the two-sentence version: Lightning is an electric current that takes the path of least resistance from the base of a cloud to the ground. Since the air it travels through is not uniform—variations in things like temperature, humidity, and pollutants determine how resistant air is to the charge—the lightning has to zig and zag to stay on that path.
Yes because, Light travels in a straight path called a light ray.
It does not, it travels as a wave
I have the straight answer from the Internet and my science teacher that light travels in the motion of waves.
Trajectory
All light travels as a wave
Light the electromagnetic wave.
In a straight line. At the speed of light.
Actually, it has been proved that light is bent by gravity, so it is impossible to prove that light travels in a straight line.
Electricity.
A laser
light travels in a straight line because it can only be bend by reflective objects.
Light behaves simultaneously as a wave and as a particle.