Why did the astronauts who walked on the moon have to use radios to talk to each other?

Answer 1

sound waves are mechanical waves that needs a medium such as air to travel through while radio waves are electromagnetic waves which doesn't need such medium to propagates. ofcourse there is air on the moon so may be the right answer is because astrounates cannot breath on the moon that's why they are using radio waves.

Answer 2

Actually, lunar surface doesn't have atmosphere and as we know, sound needs medium to propagate. Due to lack of medium, sound can't propagate on lunar surface and therefore astronauts use special type of electrical devices on their helmets which transfer sound waves from their voices into radio waves and transmit it to other astronaut. The mechanism is similar to working of radio at our homes.

Answer 3

short answer - No air.

Sound waves move by particles colliding with one and other and producing a pressure that pushes the wave away from the sound source.

Look at the image above produced by a pebble being dropped into a pond. The impact of the pebble caused the water to move away, and produced a wave that moved out from the point of impact, as the stone disappeared under the

water, the water flowed back into the hole, and a trough follows the wave, as the water bounced back up, the cycle is repeated.

This actually is a very useful illustration of how a sound wave travels. If the pebble was a book, and the pond was the floor, the pushed out medium would be air. The air would be compressed into a high pressure zone at the front of the wave, and following that will be a low pressure zone behind the wave, the resulting sound wave would for what is known as a longitudinal wave.

This compression and rarefaction of air then moves from the dropped book until it reaches our ear, where the eardrum is pushed in by each compression, and then relaxes back outward with each rarefaction. The ear sends the signal to our brain, which we interpret as a loud bang, and we jump around to see what happened.

The dropped book used its energy to create a sound wave; our eardrum took the energy of the sound wave and converted it back to mechanical energy, and the resulting electrical signal ended up in our brain. So as you can see, sound is just another form of energy, moving as a longitudinal wave, and capable of moving through air or water, and in fact, it can also even move

through solids, albeit with some loss as the walls don't tend to move as freely as air or water; A fact that makes most home owners and flat dwellers very happy.

In space there is only a vacuum (no air, or at least too little air) to compress, so sound waves do not travel. This means that some other means of communications is needed between suits.

The choices are either phone cables and phone equipment, which would limit the mobility of the crew, or Radio signals.

Radio waves, do work in a vacuum, as the signal is electro-magnetic, and magnetism works fine in a vacuum.

For this reason, electrical devices are used, and also the moon is not a great place to have a concert (unless you really don't want to hear the band)

Answer 4

To get from one place to another, sound needs material to travel through. Almost all

of the sound you hear comes to you through air.

There is no air on the moon. Two astronauts standing side-by-side on the moon could

shout at the top of their lungs and would not hear each other, because there is nothing

between them to carry the sound.