Answer:
Doppler Theory
Explanation:
it's a theory regarding the change in wave frequency during the relative motion between a wave source and its observer.
Answer:
<u>Matter is a substance that has inertia and occupies physical space. According to modern physics, matter consists of various types of particles, each with mass and size.Matter can exist in several states, also called phases. The three most common states are known as solid, liquid and gas.</u><u>Matter is the Stuff Around You</u><u> </u><u>o</u><u>r</u><u> </u><u>Atoms and compounds are all made of very small parts of matter. Those atoms go on to build the things you see and touch every day. Matter is defined as anything that has mass and takes up space (it has volume).</u><u>Solid ice, water and steam are few examples of matter touched in everyday life. Subatomic particles are also considered as matter.</u>
Answer:
Explanation:
Wave produced in string and waves produced in air are different . The only similarity is that their frequency are equal . Otherwise , no similarity . One is transverse ( on wire ) , the other is longitudinal ( air ) . Their velocities too are different .
velocity = wavelength x frequency
if frequency is constant
wavelength ∝ velocity
wavelength is proportional to velocity . Since their velocities are different , their wavelength too will be different.
The time taken by the swimmer was 1 hour.
Why?
Since the swimmer is maintaining an angle of 150° while he was swimming, there were two components of the speed (horizontal and vertical). If we want to calculate the time taken by him to cross the river, we need to calculate the vertical speed and consider that the flow's speed is compensated by his horizontal speed.
We can calculate both components of the speed using the following formula:

Now, calculating we have:

Therefore, we have that the horizontal speed is compesating the flow's speed while his vertical speed is used to cross the river which is 1 Km wide.
Hence, we have that the tame taken is:

Have a nice day!
Answer:
Yes
Explanation:
Since velocity is a vector, meaning it also relies on direction, the average speed can be different from her average velocity. An example would be if a runner turned around and ran backward after running 10 meters and returned to her starting point. If you took her average velocity of the entire trip it would actually be 0 but her average speed obviously would not be. This is why velocity can be negative but speed cannot.