# Does light travel in a straight line?

## Does light travel in a straight line?

Any physics student knows that light travels in a straight line. But now researchers have shown that light can also travel in a curve, without any external influence. Out in space, light rays passing near very massive objects such as stars are seen to travel in curves.

## Does light travel fast or slow?

The speed of light in a vacuum is 186,282 miles per second (299,792 kilometers per second), and in theory nothing can travel faster than light. In miles per hour, light speed is, well, a lot: about 670,616,629 mph.

Is sound a transverse wave?

Sound waves are not transverse waves because their oscillations are parallel to the direction of the energy transport.

### Can sound be produced in space?

Space Environment Sound travels in waves like light or heat does, but unlike them, sound travels by making molecules vibrate. On Earth, sound travels to your ears by vibrating air molecules. In deep space, the large empty areas between stars and planets, there are no molecules to vibrate. There is no sound there.

### Does light lose energy in space?

A photon doesn’t lose energy unless it collides with a particle. Photons can scatter off interstellar electrons, for example. (Perhaps you were thinking about particles, like electrons, losing energy “in transit” in a vacuum. Photons carry energy, but they don’t lose energy just because they travel.

Can a photon run out of energy?

Actually, however, there is one way that photons do lose energy as they travel through space. Because the universe is expanding, the photon’s wavelength increases very slightly over time, and in so doing loses a bit of energy. These photons are simply packets of electromagnetic energy.

## Can you have gravity without mass?

The only way to get gravity is with mass. The more mass, the more gravity you get. Without mass, you can’t have gravity. The force of gravity that we feel is actually just an acceleration towards the center of the Earth at 9.8 meters per second squared, or 1G.

## Which photon has the least energy?

Radio waves have photons with the lowest energies. Microwaves have a little more energy than radio waves. Infrared has still more, followed by visible, ultraviolet, X-rays and gamma rays.