Which of the following has the least resistance? wood iron copper silver

A train whistle has a sound intensity level of 70. dB, and a library has a sound intensity level of about 40. dB. How many times

kodGreya [7K]

Answer:

The sound intensity of train is 1000 times greater than that of the library.

Explanation:

We have expression for sound intensity level,

$L=10log_{10}\left ( \frac{I}{I_0}\right )$

A train whistle has a sound intensity level of 70 dB

We have

$70=10log_{10}\left ( \frac{I_1}{I_0}\right )$

A library has a sound intensity level of about 40 dB

We also have

$40=10log_{10}\left ( \frac{I_2}{I_0}\right )$

Dividing both equations

$\frac{70}{40}=\frac{10log_{10}\left ( \frac{I_1}{I_0}\right )}{10log_{10}\left ( \frac{I_2}{I_0}\right )}\\\\\frac{7}{4}=\frac{log_{10}\left ( \frac{I_1}{I_0}\right )}{log_{10}\left ( \frac{I_2}{I_0}\right )}\\\\10^7\frac{I_2}{I_0}=10^4\frac{I_1}{I_0}\\\\\frac{I_1}{I_2}=10^3=1000$

The sound intensity of train is 1000 times greater than that of the library.

3 0

2 years ago

I need help in this small question:

Natali5045456 [20]

Answer:

1) The energy released during nuclear fission or fusion, especially when used to generate electricity is called nuclear energy.

2) It is not renewable because it is an element that has no way whatsoever to regenerate or replicate itself, nor gets created by any natural terrestrial means, neither makes itself available by arriving from outer space (like sunlight). There is a limited amount of it available on the Earth, and every bit you use is a bit you’ll never have available again (as Uranium atoms get destroyed by the fission process).

Hope this helps You

Please mark as brainliest

Thank You

5 0

3 years ago

A 6.0 m section of wire carries a current of 5.2 A from east to west in the earth's magnetic field of 1.0 × 105 T at a location

NNADVOKAT [17]

Well, since you only want direction, ignore the numbers. Use the right hand rule.
Current (pointer finger) points west (left).
Magnetic field (middle finger) points south (towards you).
Force (thumb) then points up (away from the earth)

4 0

3 years ago

Which part of the eye holds eye color?

Anna [14]

Hi, it’s the iris. Hope this helped u

6 0

3 years ago

The tin can with water in its bottom is heated to boil water and the steam is allowed to escape for some time. The open mouth is

Norma-Jean [14]

Explanation:

Water does expand with heat (and contract with cooling), but the amount of expansion is pretty small. So when you boil a can filled with water and seal it, the water will contract slightly as it cools. The can may kink slightly, but that will be it. Actually, most likely the only things you will be able to see is then top and bottom will be sucked in and go concave. Just like a commercial can of beans.

Now if you have a can with a little water and a big air space, things are completely different.

As the water boils, water vapour is given off. Steam. Let it boils for a minute just to make sure (nearly) all the air is expelled and the can is filled with steam.

Now when you put the lid on and cool the can, that steam condenses back to water, and goes from filling the can to a few drops of water. The can is now filled (if that is the right word) with a near vacuum, The air pressure, 15 lbs/square inch, will be pressing on every surface of the can, with nothing inside the can to resist it.

The can will crumple before your eyes.

6 0

3 years ago