Answer:
v = 3200 m/s
Explanation:
As we know that the frequency of the sound wave is given as

wavelength of the sound wave is given as

so now we have

so we will have


The refractive index of water is

. This means that the speed of the light in the water is:

The relationship between frequency f and wavelength

of a wave is given by:

where v is the speed of the wave in the medium. The frequency of the light does not change when it moves from one medium to the other one, so we can compute the ratio between the wavelength of the light in water

to that in air

as

where v is the speed of light in water and c is the speed of light in air. Re-arranging this formula and by using

, we find

which is the wavelength of light in water.
Answer:
• riding on a Ferris wheel whose entrance and exit are the same
• walking around the block, starting from and ending at the same house
• running exactly one lap around a racetrack
Explanation:
Displacement simply means the.change in position of an object. In a situation whereby the initial and final position are thesame, the displacement will be zero.
The statements that describe a situation with a displacement of zero include:
• riding on a Ferris wheel whose entrance and exit are the same
• walking around the block, starting from and ending at the same house
• running exactly one lap around a racetrack
Answer:
Burning Paper
Explanation:
This is a chemical reaction, because new substances are formed
Answer:
5 mg, 
Explanation:
First of all, let's rewrite the mass in grams using scientific notation.
we have:
m = 0.005 g
To rewrite it in scientific notation, we must count by how many digits we have to move the dot on the right - in this case three. So in scientific notation is

If we want to convert into milligrams, we must remind that
1 g = 1000 mg
So we can use the proportion

and we find
